Classic Yellow Cake
Tamizar la harina, el polvo de hornear y la sal. Dejar de lado.
Separar los huevos . Dejar de lado.
Cream the butter in a large bowl with an electric mixer until fluffy and light in color, about 2 minutes on medium speed. Add the sugar and continue to mix until fluffy and light. Add the egg yolks, one at a time, being sure each is well incorporated before adding the next one. Add the vanilla.
Reduce the mixer speed to low and add the dry ingredients alternately with the sour cream, beginning and ending with flour. Be sure the mixture is completely blended after each addition. Scrape the sides of the bowl, and beat for 1 minute.
In a separate bowl, with clean beaters, beat the egg whites to soft peaks. Gently fold the whipped egg whites into the batter with a rubber spatula.
Pour the batter into the prepared pans and smooth with a rubber spatula. Bake in the preheated oven for 45 to 50 minutes for 8-inch-round pans. The top of the cake should be nicely browned. Test for doneness with a skewer or toothpick - the tester should come out dry and clean.