This is a recipe for the classic birthday cake: vanilla cake with chocolate frosting. The frosting is made with a combination of milk chocolate and cocoa for a deep chocolate flavour with a little tang from some sour cream. The vanilla cake recipe yields buttery vanilla cake layers that are perfect for any frosting.
Preheat the oven to 350 °F (175 °C). Grease, flour and line with parchment three 6x2-inch (15x5-cm) round cake pans (Amazon).
Sift together the flour, baking powder, and salt into a medium bowl and set aside.
In the bowl of an electric mixer fitted with the paddle attachment, cream together the butter and the sugar for 3 minutes until it's creamy.
Add the eggs, one at a time, scraping down the bowl as needed. Beat well between each addition. After all the eggs are added, add the vanilla and beat for an additionnal 2 to 3 minutes to lighten it. Scrape down the sides of the bowl.
Drop in one third of the flour, then mix on low, followed by half the milk, again mixing it in on low. Scrape down the sides of the bowl.
Add in half the remaining flour, mixing it into the batter on low, the remaining milk, then turn off the mixer and remove it from the stand. Finish adding the last of the flour with the spatula by hand, being sure not to overmix. Divide the batter between the 3 pans, smooth the surface and bang them on the counter to push out any air pockets. Bake the cakes on the middle rack for about 25 to 30 minutes, until the edges are golden brown and begin to pull away from the pan. Use a cake tester to ensure the centre is baked through.
Cool 15 minutes, then unmold on a rack to cool completely.
To make the frosting
Melt the chocolate with the butter on medium power in the microwave. Heat for 1 minute at a time to make sure you don't burn the chocolate. Stir to combine, add the vanilla, and let cool slightly.
Meanwhile, combine the powdered sugar with the cocoa powder in the mixer. Pour in the melted chocolate mixture and the sour cream, then beat the frosting for several minutes to combine the ingredients and lighten the mixture.
To assemble the cake
With a serrated knife, level the tops of the cakes. Plop the first levelled cake on the cake stand (or plate), cut-side down, then slather the surface with ½ cup of the frosting just to the edge. Top with a second levelled cake, and slather with another ½ cup of frosting. Top with the 3rd levelled cake, and another ½ cup of frosting. Smooth it nicely. Dirty frost the sides with ¼ cup of the remaining frosting (about half of what's left). Chill 30 minutes, then finish frosting the sides with the last of the frosting.
Notes
Makes one 6-inch layer cake
Calories calculated based on one-twelfth of the cake+frosting
For the frosting, I used Alunga milk chocolate from Cacao Barry, which you can buy at IGA stores in Quebec and online from Vanilla Food Company who deliver!
For the cocoa powder, I like Cacao Barry extra brute cocoa, which you can find on Amazon. Feel free to use any cocoa powder. They all should work here.