Ingredients:
- 2.25 cups cake flour
- 0.75 cup granulated cane sugar
- 1 tbsp baking powder
- 0.5 tsp salt
- 0.75 cup whole milk
- 0.5 cup unsalted butter
- 3 large eggs
- 2 tsp pure vanilla extract
- 1 tsp almond extract
- 2 cups fresh raspberries
- 2 cups fresh blueberries
- 2 tbsp lemon juice
- 1 tbsp cornstarch
- 2 cups heavy whipping cream
- 8 oz mascarpone cheese
- 0.5 cup powdered sugar
- 1 tsp vanilla bean paste
Instructions:
- Preheat oven to 350°F (175°C). Grease three 8-inch round cake pans and line the bottoms with parchment paper.
- Cream the softened unsalted butter and granulated cane sugar until pale and fluffy.
- Incorporate eggs one at a time, then stir in the vanilla and almond extracts.
- Sift in the cake flour, baking powder, and salt, alternating the addition with the room temperature whole milk.
- Pour batter evenly into the three pans and bake for 25–30 minutes until a toothpick comes out clean and edges are pale golden. Cool completely.
- In a small saucepan, simmer a handful of raspberries with lemon juice until broken down. Whisk in a cornstarch slurry (cornstarch mixed with water) and simmer until thickened.
- Fold in the remaining fresh raspberries and blueberries. Let the berry filling cool to room temperature.
- In a chilled bowl, beat chilled mascarpone and sifted powdered sugar until smooth.
- Slowly pour in ice-cold heavy whipping cream and vanilla bean paste. Whip on medium-high speed until stiff peaks form.
- Place one cake layer on a plate. Pipe a dam of mascarpone cream around the edge, fill the center with the berry mixture, and top with the next cake layer. Repeat and frost the exterior with the remaining cream.
- Chill the assembled cake for 4 hours before serving to ensure structural stability.