Step 1: Make the Lemon Curd

1. In a small pot, whisk together 2 whole eggs, 2 egg yolks, 100 g granulated sugar, and the juice of 1 lemon.

2. Heat over medium heat, stirring constantly with a spatula, until the mixture thickens into a gel-like consistency (10–15 minutes). It should part when you drag a spatula through it and slowly come back together.

3. Remove from heat and stir in 70 g cubed butter, one piece at a time, until fully melted and glossy.

4. Optionally, strain the curd through a fine-mesh sieve to remove any lumps of cooked egg.

5. Transfer to a small bowl, cover with plastic wrap pressed against the surface, and cool completely in the fridge (about 1–2 hours).

6. Tip: Stir constantly to prevent the eggs from scrambling, and keep the heat medium to avoid curdling.

Step 2: Prep the Pan

1. Line a 9×9-inch square pan with two sheets of parchment paper in a cross shape, leaving overhangs for easy removal.

2. Secure the parchment with binder clips to the pan’s rim. Set aside.

3. Tip: The overhangs make lifting the tiramisu out easier, so ensure they’re long enough.

Step 3: Make the Mascarpone Cream

1. In a large mixing bowl, whisk together 3 egg yolks and 70 g granulated sugar until combined.

2. Create a double boiler: Fill a small pot with 1 inch of water and bring to a boil, then turn off the heat.

3. Place the bowl with the egg yolk mixture over the pot (not touching the water) and whisk until the sugar dissolves and the mixture is warm, fluffy, and pale (5–7 minutes).

4. Remove from heat and immediately whisk in 225 g softened mascarpone cheese until smooth and lump-free.

5. In another large bowl, beat 350 g whipping cream and 1 teaspoon vanilla extract with an electric hand mixer until firm peaks form (3–5 minutes).

6. Gently fold the whipped cream into the mascarpone mixture with a spatula until no streaks remain. Set aside.

7. Tip: Ensure the mascarpone is at room temperature to avoid lumps, and fold gently to keep the cream airy.

Step 4: Assemble the Tiramisu

1. Pour 225 g limoncello into a wide, shallow bowl.

2. Dip each of the 24 ladyfingers briefly (1 second per side) into the limoncello, letting excess drip off. Arrange 12 ladyfingers in a single layer to cover the bottom of the lined pan.

3. Spread half of the mascarpone cream over the ladyfingers, smoothing it with a spatula.

4. Dip and arrange another layer of 12 ladyfingers on top, matching the bottom layer’s orientation.

5. Spread the remaining mascarpone cream over the second layer, smoothing it evenly.

6. Tip: Don’t oversoak the ladyfingers—they should be moist but not soggy to hold their shape.

Step 5: Add the Lemon Curd

1. Transfer the cooled lemon curd to a piping bag and snip off the tip.

2. Pipe an even layer of lemon curd over the top mascarpone layer, gently smoothing with an offset spatula. Be careful not to disturb the cream below.

3. Tip: If you don’t have a piping bag, spoon the curd gently and spread slowly to avoid mixing layers.

Step 6: Chill and Serve

1. Cover the pan with plastic wrap and chill in the fridge for at least 6 hours, preferably overnight, to let the flavors meld and the layers set.

2. Lift the tiramisu out using the parchment overhangs. Slice into squares or rectangles.

3. Serve as is or garnish with dollops of whipped cream and lemon slices for extra flair.

4. Tip: Use a sharp knife and wipe it clean between cuts for neat slices.