Make & cool the raspberry sauce by preparing according to the recipe. Allow the raspberry sauce to cool completely and chill for at least 30 minutes before using.

Preheat oven to 350°F. Line the base of two 8-inch round cake pans with parchment paper.

Sift flour, baking powder, baking soda, and salt into a medium bowl and whisk to blend evenly.

Combine soft butter, oil, sugar, and vanilla in a large bowl and beat with an electric hand mixer for 2 minutes until pale and fluffy. Beat in egg until well incorporated. Add egg whites and beat until well combined and smooth. Mix in sour cream.

Sift in half of the flour over the wet mixture and mix it in slowly. Gradually beat in half of the milk. Mix in remaining flour and then the rest of the milk. Beat on high for the last 5 seconds to emulsify the batter. Gently fold in raspberries.

Divide the batter evenly between the prepared pans and bake for 25-30 minutes until lightly golden and a skewer inserted into the center comes out clean.

Transfer pans to a wire rack and let cool for 20-30 minutes in the pan, then run an offset spatula or knife around the edges to loosen them, invert, remove the bottom layer of parchment, and let cool completely on the racks.

Make the frosting by placing chopped white chocolate into a large bowl. Pour ½ cup of cream into a saucepan with the scraped vanilla bean seeds and heat over medium until simmering. Pour it over the chocolate, cover, and let stand for 2 minutes. Whisk until smooth.

Let it cool for 5 minutes and whisk in the remaining cold cream. Chill in the fridge for at least 2 hours or overnight.

Once chilled, add the vanilla extract and beat until thick and fluffy.

Place one cake layer on a serving plate. Pipe around the circumference of the cake with frosting to build a wall. Spread 1 cup of raspberry filling over the top within the frosting border.

Place the other layer on top to align with the sides of the bottom layer. Cover the entire cake with frosting and use an offset spatula to smooth the sides and decorate the top.

Dollop small spoonfuls of raspberry on top and swirl if desired. Decorate with fresh raspberries.