Weigh out the ingredients
I
For the cake, you'll need flour, sugar, butter, cocoa powders, sour cream, eggs, peppermint extract, oil, vanilla, baking powder, and salt.
Weigh out the ingredients
II
For the buttercream, you'll need butter, sugar, egg yolks, white chocolate, water, and vanilla.
In a medium bowl, whisk together the flour, cocoa powders, baking powder, and salt. Set aside.
Mix dry ingredients
III
In the bowl of a stand mixer fitted with the paddle attachment, cream together the butter and sugar for 2-3 minutes until light & fluffy.
Cream butter & sugar
IV
Mixing on low speed, add the eggs one at a time, then mix in the vanilla and peppermint extract. Add half of the dry ingredients and mix, then add in the sour cream and oil, then the remaining dry ingredients.
Add wet ingredients
V
Divide the batter between the prepared cake pans and smooth them out into even layers with an offset spatula.
Divide batter
VI
Bake the cakes for about 35-40 minutes or until the edges begin to pull away from the sides of the pan and a toothpick inserted comes out clean. Turn the cakes out onto a wire rack to cool completely.
Bake & cool
VII
Melt the chocolate and let cool, then whisk the egg yolks and sugar together until thick and foamy.
Melt chocolate & mix eggs
VIII
Heat the sugar and water until the sugar dissolves, then bring to a boil. Slowly add sugar syrup into the egg yolks and mix until cooled down. Add the butter a few cubes at a time, then add the cooled melted white chocolate and vanilla until completely smooth.
Make the frosting
IX
Cut cake layers in half to make four layers. Spread buttercream in an even layer on one cake layer, then add another cake layer on top and repeat process. Frost the cake as desired, add crushed peppermint, and enjoy!
Assemble cake
X