4 cups plus 2 tablespoons cake flour (not self-rising)
2 teaspoons baking powder
1 1/2 teaspoons baking soda
1 teaspoon table salt
1 cup unsalted butter, softened
2 cups sugar
2 teaspoons pure vanilla extract
4 large eggs, at room temperature
2 cups buttermilk, well-shaken
1) Preheat oven to 350°F. Butter two 9-inch round cake pans and line with circles of parchment paper, then butter parchment. (Alternately, you can use a cooking spray, either with just butter or butter and flour to speed this process up.)
2) Sift together flour, baking powder, baking soda, and salt in a medium bowl.
3) In a large mixing bowl, beat butter and sugar with an electric mixer at medium speed until pale and fluffy, then beat in vanilla.
4) Add eggs 1 at a time, beating well and scraping down the bowl after each addition.
5) At low speed, beat in buttermilk until just combined (mixture will look curdled). Add flour mixture in three batches, mixing until each addition is just incorporated.
6) Spread batter evenly in cake pan, then rap pan on counter several times to eliminate air bubbles. Bake until golden and a wooden pick inserted in center of cake comes out clean, 35 to 40 minutes.