Introduction
Craving a warm, comforting dessert that’s bursting with tart rhubarb and a crunchy, gluten-free topping? Oat & Brown Sugar Gluten-Free Rhubarb Crisp is a delightful balance of tangy rhubarb filling and a sweet, oaty crumble, perfect for spring or summer gatherings. This recipe is naturally gluten-free, using oats and tapioca starch, and can be baked in the oven or grilled for a smoky twist. Serve it with vanilla ice cream for an irresistible treat. Ready to whip up a crowd-pleasing dessert? Let’s get baking (or grilling)!
Overview: Why This Gluten-Free Rhubarb Crisp Is Special
This Gluten-Free Rhubarb Crisp combines the tart vibrancy of rhubarb with a nutty, brown sugar-oat topping that’s both crispy and chewy. The gluten-free ingredients—oats, oat flour, and tapioca starch—ensure everyone can enjoy it, while pepitas and sunflower seeds add unique texture and flavor. The option to bake in the oven or cook on a grill makes it versatile for any setting, from cozy kitchens to backyard barbecues. Quick to prep and naturally adaptable, this crisp is ideal for casual desserts or special occasions.
- Time Requirement: 15 minutes prep, 40 minutes (oven) or 45-50 minutes (grill) cooking, 20-30 minutes cooling, ~1.5 hours total.
- Difficulty Level: Easy. Suitable for beginners with basic baking skills.
- Why It’s Special: This crisp is gluten-free, packed with tart rhubarb and a crunchy topping, and offers oven or grill options for flexibility. It’s simple, wholesome, and perfect with ice cream.
Whether you’re gluten-free or just love rhubarb, this Oat & Brown Sugar Gluten-Free Rhubarb Crisp is a delicious, fuss-free dessert.
Essential Ingredients
This Gluten-Free Rhubarb Crisp uses wholesome, gluten-free ingredients for a perfect balance of tart and sweet. Here’s what you need and why each one matters:
Filling
- Rhubarb (scant 5 cups, 575 grams, cut into 1-inch pieces on the diagonal): The star, providing tart flavor and juicy texture; diagonal cuts add visual appeal.
- Organic Cane Sugar (½ cup): Sweetens the tart rhubarb, balancing flavors.
- Tapioca Starch (2 tablespoons): Thickens the filling, creating a glossy, cohesive texture; gluten-free alternative to cornstarch.
- Lemon Juice (from 1 lemon, ~2-3 tablespoons): Enhances tartness and brightens the rhubarb’s flavor.
- Vanilla Extract (1½ teaspoons): Adds warmth and depth to the filling.
- Pinch of Salt: Elevates and balances the sweet-tart flavors.
Crisp Topping
- Old-Fashioned Oats (½ cup, 55 grams): Provides chewy, hearty texture; ensure certified gluten-free for safety.
- Oat Flour (½ cup, 50 grams): Adds structure and a nutty flavor; gluten-free binding agent.
- Tapioca Starch (1 tablespoon): Enhances crispiness in the topping.
- Raw Pepitas (¼ cup, finely ground, or ¼ cup almond flour): Adds nutty flavor and crunch; ground pepitas keep it nut-free.
- Raw Sunflower Seeds (¼ cup): Contributes texture and subtle nuttiness.
- Brown Sugar (⅓ cup, not packed): Brings caramel-like sweetness to the topping.
- Granulated Sugar (2 tablespoons): Adds extra sweetness and crisp texture.
- Fine Sea Salt (¼ teaspoon): Balances sweetness and enhances flavors.
- Cinnamon (¼ teaspoon): Adds warm, spiced notes.
- Unsalted Butter (5 tablespoons, melted): Binds the topping, creating a golden, crispy finish.
Substitutions and Variations
- Rhubarb: Use frozen rhubarb (thawed and drained) or add 1 cup strawberries or apples for a sweeter filling (adjust sugar to ⅓ cup if sweeter fruit is added).
- Cane Sugar: Swap for coconut sugar or granulated sugar; maple syrup (⅓ cup) works but may make the filling wetter.
- Tapioca Starch: Replace with cornstarch or arrowroot powder (same amount) if not gluten-free.
- Lemon Juice: Use bottled lemon juice or 1 teaspoon apple cider vinegar for tartness.
- Vanilla Extract: Omit or use ½ teaspoon almond extract for a different flavor.
- Oats/Oat Flour: Ensure certified gluten-free; swap oat flour for rice flour or more ground oats (blend oats to a powder).
- Pepitas/Almond Flour: Use ground sunflower seeds, walnuts, or omit for a simpler topping (increase oats by ¼ cup).
- Sunflower Seeds: Swap for chopped pecans, almonds, or omit (increase pepitas or oats by ¼ cup).
- Brown Sugar: Use coconut sugar or all granulated sugar for a lighter flavor.
- Butter: Replace with coconut oil or vegan butter for dairy-free; solid coconut oil may need slight warming.
- Cinnamon: Swap for nutmeg, cardamom, or omit for a plainer topping.
Pro Tip: Weigh rhubarb (575 grams) for accuracy, as volume can vary; use certified gluten-free oats to avoid cross-contamination. Grind pepitas finely for a flour-like texture if not using almond flour.
Essential Equipment
- 9 or 10-inch Baking Dish or 10-inch Cast Iron Skillet: For baking the crisp; cast iron adds a rustic touch.
- Mixing Bowls: For combining filling and topping ingredients.
- Whisk: To blend dry topping ingredients evenly.
- Coffee Grinder or Food Processor (optional): For grinding pepitas if not using almond flour.
- Oven or Grill: For baking or grilling the crisp.
- Foil (for grill): To cover during initial grilling.
- Spatula or Spoon: For mixing and spreading topping.
Pro Tip: Preheat the baking dish or skillet briefly to help the filling cook evenly; use a cast iron skillet for a crispy edge.
Step-by-Step Instructions
Making Oat & Brown Sugar Gluten-Free Rhubarb Crisp is simple, with options for oven or grill cooking. Follow these steps for a perfect dessert:
- Prepare for Baking:
- For oven: Preheat to 375°F (190°C).
- For grill: Turn on the left and middle burners, leaving one side unheated. Preheat to 400°F (204°C).
- Tip: Ensure steady grill temperature; use an oven thermometer for accuracy if needed.
- Make the Filling:
- In a large bowl, combine scant 5 cups (575 grams) chopped rhubarb, ½ cup organic cane sugar, 2 tablespoons tapioca starch, juice of 1 lemon, 1½ teaspoons vanilla extract, and a pinch of salt.
- Stir well and let sit while preparing the topping to release juices.
- Tip: Toss thoroughly to coat rhubarb; let sit 5-10 minutes for better flavor meld.
- Prepare the Crisp Topping:
- In a separate bowl, whisk together ½ cup old-fashioned oats, ½ cup oat flour, 1 tablespoon tapioca starch, ¼ cup ground pepitas (or almond flour), ¼ cup raw sunflower seeds, ⅓ cup brown sugar, 2 tablespoons granulated sugar, ¼ teaspoon fine sea salt, and ¼ teaspoon cinnamon.
- Stir in 5 tablespoons melted unsalted butter until fully combined and crumbly.
- Tip: Use a fork to mix butter for an even, clumpy texture; avoid overmixing to keep it crumbly.
- Assemble the Crisp:
- Add the rhubarb filling to a 9 or 10-inch baking dish or 10-inch cast iron skillet, spreading evenly.
- Sprinkle the topping over the filling, leaving a ½-inch border around the edges to let the rhubarb peek through.
- Tip: Pat topping gently to adhere; the border ensures a pretty, bubbly appearance.
- Cook the Crisp:
- Oven Method:
- Place the dish on the middle rack and bake for 40 minutes, until the fruit is softened, bubbling, and the topping is golden brown.
- Check at 35 minutes; cover with foil if topping browns too quickly.
- Grill Method:
- Place the dish on the unheated side of the grill (indirect heat). Cover with foil and close the grill lid.
- Bake for 20 minutes, then remove foil and rotate the pan clockwise.
- Continue baking for 25-30 minutes, until bubbling and the topping is lightly browned.
- Tip: For oven, rotate halfway for even baking; for grill, check heat to maintain 400°F and avoid hot spots.
- Oven Method:
- Cool and Serve:
- Let the crisp cool for 20-30 minutes to set the filling and enhance flavors.
- Serve warm with a scoop of vanilla ice cream or whipped cream (makes 6-8 servings).
- Tip: Cooling prevents burns and thickens the filling; reheat briefly if serving later.
Cooking Tips:
- Check Doneness: Look for bubbling fruit and a golden topping; rhubarb should be fork-tender.
- Prevent Soggy Topping: Leave the border to let steam escape; don’t pack topping too tightly.
- Grill Safety: Use oven mitts and keep the grill lid closed to maintain heat; foil helps initially to cook the filling.
Assembly: Serving Your Gluten-Free Rhubarb Crisp
Serving Oat & Brown Sugar Gluten-Free Rhubarb Crisp is all about highlighting its warm, tart, and crunchy appeal:
- Serve Warm:
- Serve ¾-1 cup per person as a dessert, ideally with vanilla ice cream or whipped cream.
- Tip: Warm crisp enhances the contrast with cold ice cream; reheat leftovers for best texture.
- Presentation Tips:
- Scoop into bowls, ensuring a mix of juicy filling and crispy topping.
- Garnish with a mint sprig or a dusting of cinnamon for a rustic look.
- Serve in the baking dish or skillet for a cozy, family-style presentation.
- Serving Ideas:
- Pair with coffee, tea, or a glass of dessert wine for an elegant finish.
- Serve with yogurt or crème fraîche for a breakfast twist.
- Offer at potlucks or barbecues alongside other desserts like berry cobbler or lemon bars.
- Portioning:
- Makes 6-8 servings (¾-1 cup each) from a 9 or 10-inch dish.
- Serve smaller portions (½ cup) with extra toppings for 10-12 as a light dessert.
Pro Tip: Drizzle with a touch of honey or caramel sauce for extra decadence when serving.
Storage and Make-Ahead Tips
This Gluten-Free Rhubarb Crisp stores well and can be prepped ahead:
- Storage:
- Room Temperature: Store covered for up to 1 day if serving soon; best fresh.
- Fridge: Store in an airtight container or covered dish in the refrigerator for up to 4-5 days.
- Freezer: Freeze baked crisp (whole or portioned) in a freezer-safe container for up to 2 months. Thaw in the fridge overnight before reheating.
- Reheating:
- Oven: Reheat at 350°F for 10-15 minutes, covered with foil, until warm. Uncover for the last 5 minutes to crisp the topping.
- Microwave: Heat individual portions for 30-60 seconds, but topping may soften.
- Air Fryer: Reheat at 325°F for 5-7 minutes for a crispy topping.
- Tip: Add a sprinkle of fresh oats or nuts before reheating to revive crunch.
- Make-Ahead:
- Prepare filling and topping separately up to 1 day ahead; store covered in the fridge and assemble before baking.
- Assemble the entire crisp (unbaked) up to 4 hours ahead, cover, and refrigerate; bake fresh.
- Chop rhubarb and grind pepitas a day ahead to save time.
- Tip: Bake just before serving for the crispiest topping; grilled crisps are best fresh.
Pro Tip: Freeze leftover crisp in single-serve portions for quick desserts; reheat with a scoop of ice cream for instant indulgence.
Recipe Variations
Make Oat & Brown Sugar Gluten-Free Rhubarb Crisp your own with these twists:
- Strawberry Rhubarb Crisp: Add 1 cup chopped strawberries to the filling, reduce rhubarb to 4 cups, and cut sugar to ⅓ cup.
- Nutty Rhubarb Crisp: Replace sunflower seeds with chopped pecans or almonds; swap pepitas for hazelnut flour.
- Spiced Rhubarb Crisp: Add ¼ teaspoon ginger or nutmeg to the topping for extra warmth.
- Vegan Rhubarb Crisp: Use coconut oil or vegan butter instead of butter; ensure ice cream is dairy-free.
- Low-Sugar Rhubarb Crisp: Reduce brown sugar to ¼ cup and granulated sugar to 1 tablespoon; add 1 tablespoon maple syrup for sweetness.
Healthier Twist:
- Use coconut sugar or monk fruit sweetener instead of brown/granulated sugar (1:1 ratio).
- Increase sunflower seeds or pepitas to ⅓ cup each and reduce butter to 3 tablespoons for less fat.
- Add 2 tablespoons ground flaxseed to the topping for extra fiber and omega-3s.
- Serve with Greek yogurt instead of ice cream for a protein boost.
Conclusion
Oat & Brown Sugar Gluten-Free Rhubarb Crisp is a warm, tangy, and crunchy dessert that’s perfect for any occasion. With its gluten-free oat topping, tart rhubarb filling, and versatile oven or grill options, it’s a wholesome, crowd-pleasing treat that’s easy to make. Serve it with vanilla ice cream for a classic finish, and enjoy the flavors of spring in every bite. Grab your rhubarb and let’s create a dessert that’s as delicious as it is inclusive! What’s your favorite way to top this rhubarb crisp?
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Oat & Brown Sugar Gluten-Free Rhubarb Crisp
Description
Craving a warm, comforting dessert that’s bursting with tart rhubarb and a crunchy, gluten-free topping? Oat & Brown Sugar Gluten-Free Rhubarb Crisp is a delightful balance of tangy rhubarb filling and a sweet, oaty crumble, perfect for spring or summer gatherings
Ingredients
Filling
- Rhubarb (scant 5 cups, 575 grams, cut into 1-inch pieces on the diagonal): The star, providing tart flavor and juicy texture; diagonal cuts add visual appeal.
- Organic Cane Sugar (½ cup): Sweetens the tart rhubarb, balancing flavors.
- Tapioca Starch (2 tablespoons): Thickens the filling, creating a glossy, cohesive texture; gluten-free alternative to cornstarch.
- Lemon Juice (from 1 lemon, ~2-3 tablespoons): Enhances tartness and brightens the rhubarb’s flavor.
- Vanilla Extract (1½ teaspoons): Adds warmth and depth to the filling.
- Pinch of Salt: Elevates and balances the sweet-tart flavors.
Crisp Topping
- Old-Fashioned Oats (½ cup, 55 grams): Provides chewy, hearty texture; ensure certified gluten-free for safety.
- Oat Flour (½ cup, 50 grams): Adds structure and a nutty flavor; gluten-free binding agent.
- Tapioca Starch (1 tablespoon): Enhances crispiness in the topping.
- Raw Pepitas (¼ cup, finely ground, or ¼ cup almond flour): Adds nutty flavor and crunch; ground pepitas keep it nut-free.
- Raw Sunflower Seeds (¼ cup): Contributes texture and subtle nuttiness.
- Brown Sugar (⅓ cup, not packed): Brings caramel-like sweetness to the topping.
- Granulated Sugar (2 tablespoons): Adds extra sweetness and crisp texture.
- Fine Sea Salt (¼ teaspoon): Balances sweetness and enhances flavors.
- Cinnamon (¼ teaspoon): Adds warm, spiced notes.
- Unsalted Butter (5 tablespoons, melted): Binds the topping, creating a golden, crispy finish.
Substitutions and Variations
- Rhubarb: Use frozen rhubarb (thawed and drained) or add 1 cup strawberries or apples for a sweeter filling (adjust sugar to ⅓ cup if sweeter fruit is added).
- Cane Sugar: Swap for coconut sugar or granulated sugar; maple syrup (⅓ cup) works but may make the filling wetter.
- Tapioca Starch: Replace with cornstarch or arrowroot powder (same amount) if not gluten-free.
- Lemon Juice: Use bottled lemon juice or 1 teaspoon apple cider vinegar for tartness.
- Vanilla Extract: Omit or use ½ teaspoon almond extract for a different flavor.
- Oats/Oat Flour: Ensure certified gluten-free; swap oat flour for rice flour or more ground oats (blend oats to a powder).
- Pepitas/Almond Flour: Use ground sunflower seeds, walnuts, or omit for a simpler topping (increase oats by ¼ cup).
- Sunflower Seeds: Swap for chopped pecans, almonds, or omit (increase pepitas or oats by ¼ cup).
- Brown Sugar: Use coconut sugar or all granulated sugar for a lighter flavor.
- Butter: Replace with coconut oil or vegan butter for dairy-free; solid coconut oil may need slight warming.
- Cinnamon: Swap for nutmeg, cardamom, or omit for a plainer topping.
Pro Tip: Weigh rhubarb (575 grams) for accuracy, as volume can vary; use certified gluten-free oats to avoid cross-contamination. Grind pepitas finely for a flour-like texture if not using almond flour.
Essential Equipment
- 9 or 10-inch Baking Dish or 10-inch Cast Iron Skillet: For baking the crisp; cast iron adds a rustic touch.
- Mixing Bowls: For combining filling and topping ingredients.
- Whisk: To blend dry topping ingredients evenly.
- Coffee Grinder or Food Processor (optional): For grinding pepitas if not using almond flour.
- Oven or Grill: For baking or grilling the crisp.
- Foil (for grill): To cover during initial grilling.
- Spatula or Spoon: For mixing and spreading topping.
Pro Tip: Preheat the baking dish or skillet briefly to help the filling cook evenly; use a cast iron skillet for a crispy edge.
Instructions
- Prepare for Baking:
- For oven: Preheat to 375°F (190°C).
- For grill: Turn on the left and middle burners, leaving one side unheated. Preheat to 400°F (204°C).
- Tip: Ensure steady grill temperature; use an oven thermometer for accuracy if needed.
- Make the Filling:
- In a large bowl, combine scant 5 cups (575 grams) chopped rhubarb, ½ cup organic cane sugar, 2 tablespoons tapioca starch, juice of 1 lemon, 1½ teaspoons vanilla extract, and a pinch of salt.
- Stir well and let sit while preparing the topping to release juices.
- Tip: Toss thoroughly to coat rhubarb; let sit 5-10 minutes for better flavor meld.
- Prepare the Crisp Topping:
- In a separate bowl, whisk together ½ cup old-fashioned oats, ½ cup oat flour, 1 tablespoon tapioca starch, ¼ cup ground pepitas (or almond flour), ¼ cup raw sunflower seeds, ⅓ cup brown sugar, 2 tablespoons granulated sugar, ¼ teaspoon fine sea salt, and ¼ teaspoon cinnamon.
- Stir in 5 tablespoons melted unsalted butter until fully combined and crumbly.
- Tip: Use a fork to mix butter for an even, clumpy texture; avoid overmixing to keep it crumbly.
- Assemble the Crisp:
- Add the rhubarb filling to a 9 or 10-inch baking dish or 10-inch cast iron skillet, spreading evenly.
- Sprinkle the topping over the filling, leaving a ½-inch border around the edges to let the rhubarb peek through.
- Tip: Pat topping gently to adhere; the border ensures a pretty, bubbly appearance.
- Cook the Crisp:
- Oven Method:
- Place the dish on the middle rack and bake for 40 minutes, until the fruit is softened, bubbling, and the topping is golden brown.
- Check at 35 minutes; cover with foil if topping browns too quickly.
- Grill Method:
- Place the dish on the unheated side of the grill (indirect heat). Cover with foil and close the grill lid.
- Bake for 20 minutes, then remove foil and rotate the pan clockwise.
- Continue baking for 25-30 minutes, until bubbling and the topping is lightly browned.
- Tip: For oven, rotate halfway for even baking; for grill, check heat to maintain 400°F and avoid hot spots.
- Oven Method:
- Cool and Serve:
- Let the crisp cool for 20-30 minutes to set the filling and enhance flavors.
- Serve warm with a scoop of vanilla ice cream or whipped cream (makes 6-8 servings).
- Tip: Cooling prevents burns and thickens the filling; reheat briefly if serving later.
Cooking Tips:
- Check Doneness: Look for bubbling fruit and a golden topping; rhubarb should be fork-tender.
- Prevent Soggy Topping: Leave the border to let steam escape; don’t pack topping too tightly.
- Grill Safety: Use oven mitts and keep the grill lid closed to maintain heat; foil helps initially to cook the filling.
FAQs
Q: Can I use frozen rhubarb?
A: Yes, thaw and drain frozen rhubarb to remove excess liquid. Pat dry and use as directed; baking time may increase slightly.
Q: Is this recipe truly gluten-free?
A: Yes, if using certified gluten-free oats and oat flour. Check labels for cross-contamination, especially with oats.
Q: Can I make this without tapioca starch?
A: Yes, use cornstarch or arrowroot powder (same amount) for the filling and topping; omit in the topping for a softer texture.
Q: Why is my topping soggy?
A: Too much butter, a packed topping, or excess fruit liquid can cause this. Drain rhubarb well, use exact butter, and leave a border.
Q: Can I bake this in a different dish size?
A: Yes, use an 8×8-inch dish for a thicker crisp (add 5-10 minutes baking) or a 9×13-inch for a thinner one (reduce by 5 minutes).
Q: Can I make this vegan?
A: Yes, use coconut oil or vegan butter and serve with dairy-free ice cream. Ensure sugars are vegan (some are processed with bone char).
Q: Why isn’t my filling bubbling?
A: Low oven/grill temperature or insufficient baking time may be the issue. Ensure 375°F (oven) or 400°F (grill) and bake until bubbling.
Q: Can I double the recipe?
A: Yes, double all ingredients and use a 9×13-inch dish or two 9-inch dishes. Baking time may increase by 5-10 minutes.