White Chocolate-Raspberry Cake

Instructions

• Prepare pastry cream: Puree raspberries in a blender. Strain to remove seeds. Set aside pulp; you should have 1 cup.
• Whisk egg yolks, sugar, flour, and cornstarch in a bowl until completely smooth.
• Warm cream in a small saucepan over low heat until just hot enough to steam. Once steaming, add 1/2 of it to the egg mixture, whisking constantly to avoid scrambling the eggs. Add that mixture back into the hot cream mixture and continue to heat and stir until custard is very thick, 3 to 5 minutes. Remove from the heat and stir in the reserved raspberry pulp. Let sit until cooled to room temperature, about 30 minutes. Place parchment or waxed paper over the surface to prevent a skin from forming and refrigerate, 8 hours to overnight.
• Preheat the oven to 350 degrees F (175 degrees C). Grease the sides and bottoms of two 9-inch round, metal or glass cake pans.
• Prepare cake: Blend cake mix, water, oil, and eggs in a large bowl at low speed until moistened, about 30 seconds. Beat at medium speed for 2 minutes. Pour batter into the prepared pans.
• Bake in the preheated oven until a toothpick inserted in the center comes out clean, 23 to 28 minutes. Cool in the pans on a wire rack for 15 minutes. Remove cakes from the pans and cool completely, about 15 to 20 more minutes.
• Prepare the frosting: Beat butter and confectioners' sugar in a large bowl on medium speed until creamy. Beat in melted white chocolate. Add vanilla and beat on low speed, scraping the sides and bottom of the bowl, until light and fluffy. Transfer to a piping bag fitted with a #18 star tip.
• Level the tops of the cooled cake layers with a large serrated knife. Pipe a small amount of frosting onto the center of a serving plate. Put one layer, cut-side down, on the plate. Pipe a thick ring around the top edge of that layer; this will keep the filling in the cake and prevent the layers from sliding. Spread raspberry pastry cream onto the cake. Place to remaining layer, cut-side down, on top. Frost the top and sides with remaining frosting, decorating as desired.
• Hold white chocolate bar in one hand with a paper towel (to stop it from melting in your hand). Use a vegetable peeler and slowly and carefully shave along the length of the bar to form pretty curls. Put chocolate curls on the sides of the cake and place raspberries in a ring around the top edge.