Raspberry Compote & Purée

1. Cook the raspberries in a medium saucepan over medium heat for about 10 minutes, stirring occasionally, until thick and reduced.
2. Reserve about 80 g (⅓ cup) of the compote for filling the cake layers.
3. Blend the remaining compote, then strain it through a fine sieve to remove the seeds and get a smooth raspberry purée.
4. Let the purée cool completely before using it in the cake and frostings.

Raspberry Cake Layers

1. Preheat the oven to 165°C (325°F), grease a heart-shaped cake pan, and line the bottom with parchment paper.
2. Beat the butter and sugar for 3 minutes until creamy and smooth.
3. Add the egg whites and vanilla and whip for 5 minutes until the mixture is light and fluffy.
4. Mix in the cooled raspberry purée until evenly combined.
5. Add the dry ingredients and buttermilk alternately, mixing gently until smooth.
6. Adjust the color with a small amount of pink or red food coloring if needed.
7. Divide the batter into 3 equal portions and bake one layer at a time for 20–25 minutes without opening the oven.
8. Check doneness, then cool the cake upside down on a wire rack before trimming if needed.

Raspberry Buttercream

1. Beat the softened butter for 3–4 minutes until pale and creamy.
2. Add the powdered sugar gradually and mix until smooth.
3. Mix in the vanilla extract and heavy cream until light and fluffy.
4. Add the strained raspberry purée and beat briefly until fully incorporated.
5. Let the buttercream rest at room temperature, then transfer to a large piping bag.

Raspberry Mascarpone Frosting

1. Combine all ingredients (cold mascarpone, cold cream, raspberry purée, powdered sugar, vanilla) in a bowl.
2. Whip on low speed for 1–2 minutes until smooth, thick, and stable.
3. Transfer to a piping bag and keep refrigerated until assembly.

Assembling the Raspberry Heart Cake

1. Place the first cake layer on a cake board set on a turntable.
2. Pipe a buttercream border around the edge to create a dam.
3. Fill the center with raspberry mascarpone frosting, then add raspberry compote.
4. Repeat with the remaining layers, finishing with the final cake layer.
5. Apply a thin crumb coat of raspberry buttercream and smooth it.
6. Add a second, thicker layer and smooth with a metal scraper.
7. Pipe decorative borders on the top and bottom using star tips for a vintage finish.
8. Refrigerate until ready to serve, or serve once fully set.