- Cake:
- 3 cups sifted all-purpose flour, plus more for dusting
- 1 tablespoon baking powder
- 3/4 teaspoon salt
- 1 cup milk, at room temperature
- 2 teaspoons pure vanilla extract
- 3/4 cup unsalted butter, softened
- 2 cups granulated sugar
- 4 large eggs, at room temperature
- Frosting:
- 1/2 pound unsalted butter, softened
- 1 large egg yolk (optional)
- 1 pound confectioners' sugar
- 6 tablespoons heavy cream
- 1 teaspoon pure vanilla extract
- Pinch of salt
- Make the cake: Preheat the oven to 350 degrees F. Butter two 9-by-2-inch round cake pans and line with parchment paper; butter and dust with flour. In a bowl, mix the 3 cups of flour, baking powder and salt. In a cup, mix the milk with the vanilla.
- In a standing mixer fitted with the paddle, beat the butter at medium speed until light and creamy. Add the sugar and beat until fluffy, 4 minutes. Beat in the eggs, one at a time, scraping down the bowl. Beat in the dry ingredients in 3 batches, alternating with the milk mixture and scraping down the bowl.
- Scrape the batter into the pans. Bake in the lower third of the oven for about 35 minutes, until springy. Let cool for 15 minutes, then run a knife around the edges and invert onto a rack. Peel off the paper, turn the cakes upright and cool completely.
- Make the frosting: In a standing mixer fitted with the whisk, beat the butter and egg yolk at medium-high speed until creamy. Beat in the sugar at low speed. Beat in the cream, vanilla and salt, then beat at medium-high speed until fluffy, 3 minutes longer.
- Spread 1 cup of frosting over a cake layer and top with the second layer; frost the top and sides. Let stand 1 hour; serve.