Raspberry Lemon Curd Mascarpone Layer Cake Step-by-step instructions

Before you start

Before starting, bring the butter, eggs, and buttermilk to room temperature. Grease and flour two 9-inch round cake pans, and line the bottoms with parchment paper for easy release. Measure all ingredients and have them ready. If using store-bought lemon curd, have it at room temperature.

Chill the mixing bowl and beaters for the mascarpone cream. Prepare the lemon white chocolate curls by grating the chocolate on a box grater; store in the refrigerator until needed. Slice the lemon into thin wheels and set aside. Preheat the oven to 350°F (175°C) and position a rack in the center.

Instructions

Bake the Lemon Sponge

1. 1Prepare the Lemon Sponge
   Heat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans. In a medium bowl, whisk together the flour, baking powder, and salt. In a large bowl, beat the butter and sugar until light and fluffy, about 3 minutes. Add the eggs one at a time, beating well after each addition, then beat in the vanilla and lemon zest. With the mixer on low, add the flour mixture in three additions, alternating with the buttermilk, beginning and ending with the flour.
   Look for The batter is thick and fluffy; the pans are about two-thirds full.
   Safe temperature 160°F (71°C) internal temperature (egg dishes)
   Tip Use room-temperature ingredients for a smoother batter and even rise.
2. 2Bake the Sponge Layers
   Bake for 25 to 30 minutes, until a toothpick inserted in the center comes out clean and the cakes spring back when lightly pressed. Let the cakes cool in the pans for 10 minutes, then turn them out onto a wire rack to cool completely. The internal temperature of the cakes should read 160°F (71°C) when done.
   Look for The tops are golden and a toothpick comes out clean.
   Safe temperature 160°F (71°C) internal temperature (egg dishes)
   Tip Cool the cakes completely before assembling to prevent the cream from melting.

The sponge layers are golden brown and spring back when touched. A toothpick inserted in the center comes out clean. The cakes have cooled completely on a wire rack, and the tops are level.

The kitchen smells of fresh lemon and vanilla. The layers are light, airy, and ready to be assembled. If the layers domed, use a serrated knife to level them before stacking.

Whip the Cream and Assemble

3. 3Make the Mascarpone Cream
   In a large chilled bowl, beat the mascarpone, heavy cream, confectioners' sugar, and lemon juice together until stiff peaks form. Be careful not to overbeat, as the mixture can curdle. The cream should be thick and spreadable.
   Look for The cream holds stiff peaks when the whisk is lifted.
   Tip Chill the bowl and beaters for 10 minutes before whipping for best results.
4. 4Assemble the Cake Layers
   Place one cake layer on a serving plate. Spread a generous layer of lemon curd over the top, then a layer of mascarpone cream. Scatter fresh raspberries over the cream, pressing them in slightly. Place the second cake layer on top and spread the remaining mascarpone cream over the top and sides of the cake.
   Look for The cake is evenly covered with cream, with raspberries peeking through.
   Tip Use an offset spatula to create smooth, even layers.
5. 5Chill the Assembled Cake
   Refrigerate the assembled cake for at least 30 minutes to firm up the cream before adding the glaze. This helps the glaze flow smoothly and prevents the cake from sliding.
   Look for The cream is set and firm to the touch.
   Tip Chilling also makes slicing cleaner.

The mascarpone cream is thick, glossy, and holds stiff peaks. The lemon curd and raspberries are ready. The first layer is spread with curd and cream, and raspberries are nestled in. The second layer is placed on top, and the entire cake is coated in cream, with smooth sides and an even top. The cake is chilling in the refrigerator, and the cream has firmed up.

Glaze and Garnish

6. 6Make the White Chocolate Glaze
   Place the chopped white chocolate in a heatproof bowl. Heat the heavy cream in a small saucepan until just simmering, then pour it over the chocolate. Let sit for 2 minutes, then stir until smooth and glossy. Let the glaze cool slightly until it thickens to a pourable consistency.
   Look for The glaze is smooth, glossy, and coats the back of a spoon.
   Tip If the glaze is too thick, stir in a teaspoon of warm cream.
7. 7Glaze the Cake
   Pour the white chocolate glaze over the top of the chilled cake, letting it drip down the sides. Use an offset spatula to spread it evenly, if needed. Immediately garnish with fresh raspberries, grated lemon white chocolate curls, and lemon wheels.
   Look for The glaze cascades down the sides, and the toppings are evenly distributed.
   Tip Work quickly before the glaze sets.
8. 8Chill and Serve
   Refrigerate the cake for at least 1 hour to set the glaze. To serve, slice a thick triangular wedge and lift it with a metal cake server. The layers should be distinct and the cream set.
   Look for The glaze is firm, and the cake holds its shape when sliced.
   Tip Use a sharp knife dipped in hot water for clean slices.

The white chocolate glaze is smooth and pourable, with a slight sheen. It has been poured over the chilled cake, cascading down the sides in elegant drips. Fresh raspberries, white chocolate curls, and lemon wheels are arranged on top. The cake is chilled until the glaze is set, and the finished dessert looks glossy and inviting, ready to be sliced and served.

Common mistakes

A common mistake is overmixing the sponge batter, which develops gluten and results in a dense, tough cake. Mix just until the flour is incorporated. Another issue is overwhipping the mascarpone cream, which can cause it to separate and become grainy. Stop as soon as stiff peaks form.

When spreading the cream, work gently to avoid dragging raspberries through the layers. The glaze should be slightly cooled but still pourable; if it's too hot, it will melt the cream, and if too cold, it will be too thick to spread. Chill the cake before glazing to ensure clean results.

How to tell it’s done

The cake is done when a toothpick inserted into the center comes out clean and the top springs back when lightly pressed. The internal temperature should read 160°F (71°C) for the eggs to be fully set. The mascarpone cream should hold stiff peaks and be thick enough to spread without running.

The white chocolate glaze should be smooth and pourable but not too thin; it should coat the back of a spoon. When the assembled cake is chilled, the glaze should be firm to the touch, and slicing should reveal clean, distinct layers without the cream oozing out.

• Egg dishes: 160°F (71°C) in the thickest part