This is an excellent cake, simple and delicious. It is good at room temperature or refrigerated. You can serve it with chocolate sauce, fruit, plain. It keeps well for several days.
3 cups cake flour
1 2/3 cup granulated sugar
2 1/2 tsp baking powder
3/4 tsp salt
1/2 cup sour cream
1/3 cup milk
3 large whole eggs
2 large egg yolks
1 tablespoon vanilla extract
2 1/2 sticks (10 ounces) unsalted butter, softened
1. Preheat oven to 350. Generously grease and flour a 12-cup bundt pan or tube pan. Tap out excess flour.
2. Blend cake flour, sugar, baking powder and salt in the bowl of a standing electric mixer.
3. In a medium bowl, using a fork, beat together sour cream, milk, whole eggs, yolks and vanilla until very well blended and smooth.
4. Add the butter and half the egg mixture to the dry ingredients. Beat at low speed just until thoroughly incorporated. Increase the speed to high and beat for 1 minute, do not overmix. Add the remaining egg mixture and beat at medium-high speed until the batter is fluffy and smooth, about 1 minute longer.
5. Scrape the batter into the prepared pan. Rap the pan on the counter several times to remove air bubbles. Bake the cake in the middle of the oven for 50 - 60 minutes or until it is well browned, pulls away from the pan sides and a toothpick inserted in the thickest part comes out clean. Transfer to a rack to cool completely.
6. Run a thin knife aorund the pan edges to loosen the cake and invert it onto a serving plate.