Description

Craving a warm, seasonal dish that’s perfect for autumn gatherings or a cozy dinner? What if you could layer flaky puff pastry with roasted butternut squash, savory mushrooms, and melty parmesan for a show-stopping tart? Butternut Squash & Mushroom Tart is your answer—a vegetarian masterpiece with bold fall flavors, ideal for holiday sides, brunches, or a light main course

Ingredients

Here’s the lineup for 6-8 servings (one 10×16-inch tart). Each ingredient plays a key role, with swaps for flexibility.

Dough

Homemade rough puff pastry or store-bought frozen puff pastry (1 pound, 2 sheets): Creates a flaky, buttery base. Sub: Gluten-free puff pastry or phyllo dough (layered).
Egg wash (1 large egg beaten with 1 tablespoon water or milk): Adds golden shine. Sub: Milk or plant-based milk for vegan.

Topping

Olive oil (1 tablespoon): Sautés veggies for flavor. Sub: Avocado oil or butter.
Butternut squash (2 cups, 270g, peeled and sliced 1/4-inch thick): Adds sweet, hearty texture. Sub: Acorn squash or sweet potato.
Mushrooms (1 1/4 cups, 150g, sliced or roughly chopped): Bring savory, earthy depth. Sub: Cremini, shiitake, or zucchini.
Onion (1/2 cup, 1/2 medium, sliced): Adds mild sweetness. Sub: Shallots or red onion.
Garlic (3 cloves, minced): Provides aromatic warmth. Sub: 1 teaspoon garlic powder.
Salt (1/4 teaspoon): Enhances flavors. Sub: Kosher salt or low-sodium alternatives.
Black pepper (pinch, plus more for garnish): Adds subtle heat. Sub: White pepper.
Fresh thyme leaves (2 teaspoons or 1 teaspoon dried): Brings herby brightness. Sub: Fresh or dried oregano.
Fresh rosemary (2 teaspoons chopped or 1 teaspoon dried): Adds piney depth. Sub: Fresh or dried sage.
Ground nutmeg (pinch): Enhances fall flavors with warmth. Sub: Cinnamon or allspice.
Shredded parmesan cheese (1 cup, 120g, plus more for garnish): Adds nutty, melty richness. Sub: Pecorino Romano, Gruyère, or vegan cheese.
Optional garnish: Flaky sea salt, extra pepper, cheese, thyme, or rosemary for flair. Sub: Chopped parsley or chives.

These ingredients are fall-inspired and accessible, creating a wholesome, flavorful tart.

Cook Mode Prevent your screen from going dark

Instructions

Prep the dough: If using homemade rough puff pastry, prepare through the second refrigeration (chilled and ready to roll). If using store-bought frozen puff pastry (1 pound, 2 sheets), ensure it’s thawed. Keep dough refrigerated until step 4. Tip: Thaw store-bought pastry in the fridge overnight for ease.
Cook the topping: In a large skillet over low-medium heat, heat 1 tablespoon olive oil. Add 2 cups sliced butternut squash and cook, stirring occasionally, for 5 minutes. Add 1 1/4 cups mushrooms, 1/2 cup sliced onion, 3 minced garlic cloves, 1/4 teaspoon salt, a pinch of black pepper, 2 teaspoons fresh thyme (or 1 teaspoon dried), 2 teaspoons fresh rosemary (or 1 teaspoon dried), and a pinch of nutmeg. Cook until veggies are soft, about 5-6 minutes. Remove from heat. Tip: Slice squash thinly for even cooking; stir gently to keep veggies intact.
Preheat oven: Preheat to 400°F (204°C). Line a large baking sheet with parchment paper or a silicone baking mat. Tip: Parchment prevents sticking and ensures easy cleanup.
Roll the dough: On a lightly floured surface with a lightly floured rolling pin, roll puff pastry into a 10×16-inch rectangle. For store-bought pastry, overlap the edges of two sheets and roll to adhere into one rectangle. Transfer to the lined baking sheet. Reshape into a rectangle if needed. Fold over a 1/2-inch edge and crimp with a fork. If dough is warm, chill on the baking sheet in the fridge for 10 minutes. Tip: Keep dough cold for easier crimping and flakier results.
Assemble the tart: Brush the dough (including edges) with egg wash (1 egg beaten with 1 tablespoon water or milk). Poke holes all over the dough (not the crimped edge) with a fork to prevent puffing. Sprinkle with 3/4 cup parmesan cheese. Spoon veggie topping over cheese, arranging in a single layer as best as possible. Tip: Spread veggies evenly to ensure every bite has flavor.
Bake: Bake for 30 minutes until pastry is golden. Remove from oven, sprinkle with remaining 1/4 cup parmesan, and bake 5-8 minutes more until cheese is melted and pastry is golden brown. Tip: Check at 5 minutes to avoid over-browning cheese.
Serve: Garnish with flaky sea salt, extra pepper, cheese, thyme, or rosemary, if desired. Slice into squares or rectangles and serve warm or at room temperature. Tip: Let cool for 5 minutes for easier slicing.