For the cake: Preheat the oven to 350 degrees F. Coat two 9-inch round cake pans with cooking spray.
Whisk together the flour, granulated sugar, baking powder, baking soda, salt and pudding mix in a medium bowl. Set aside. Bring the milk to a boil and add the white chocolate chips. Let stand, covered, for 5 minutes, then stir until completely incorporated. Allow the white chocolate mixture to cool completely. Beat the oil, eggs and white chocolate mixture in a large bowl with an electric mixer until fully incorporated, about 2 minutes. Add the vanilla and reduce the speed to low. Gradually add the flour mixture, beating until combined, about 3 minutes.
Divide the batter evenly among the prepared pans. Bake until golden and a toothpick inserted into the center of the cakes comes out clean, 25 to 30 minutes. Allow the cakes to cool in the pans for 10 minutes, then turn out on wire racks to cool completely, about 45 minutes.
For the raspberry filling: Combine the raspberries, sugar, lemon juice and cornstarch in a small saucepan. Place over medium-high heat and slowly bring to a boil, stirring constantly until thickened. Let cool completely, about 45 minutes.
For the chocolate ganache: Heat the heavy cream to boiling. Pour over the chocolate in a heat-proof bowl. Stir until completely smooth. Allow to cool to room temperature, about 45 minutes.
For the buttercream: Beat the butter, shortening and vanilla in a large bowl with an electric mixer until combined and smooth, about 2 minutes. Add the confectioners' sugar and beat until light and fluffy, about 2 minutes.
To assemble the cake: Level both cakes by running a sharp knife around the top edge of each cake, scoring it, then carefully cutting through the cakes along the score lines. Fill a piping back fitted with a No.12 tip with buttercream icing. Pipe a dam around the inside of the bottom layer of cake. Inside the dam, spread a very thin layer of raspberry filling, about 3 tablespoons (for this filling, less is more). Then top with a more generous layer of chocolate ganache, about a quarter-inch thick. Stack the other cake layer on top and cover the whole cake with buttercream icing.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.