Preheat oven to 350°F (175°C). Grease and line three 8-inch round cake pans.

In a large bowl, cream butter and sugar until light and fluffy. Slowly mix in oil.

Add egg whites one at a time, mixing until combined. Stir in pink gel food coloring.

In a separate bowl, whisk together cake flour, baking powder, baking soda, and salt.

Alternate adding dry ingredients and milk to the butter mixture, beginning and ending with the dry. Gently fold in sour cream and vanilla.

Divide batter evenly among prepared pans and bake 25–28 minutes, or until a toothpick inserted comes out clean. Cool completely.

For the frosting: beat butter until fluffy. Gradually mix in powdered sugar, then raspberry emulsion, salt, and enough cream to reach spreadable consistency.

Assemble: layer cakes with frosting between each, apply a crumb coat, chill, then frost with the remaining buttercream. Garnish with fresh raspberries.