Step 1

Preheat the oven to 350°F. Line two 8" cake pans (don't use non-stick pans) with a circle of parchment paper or butter and flour the bottom of pans only. Do not butter and flour the sides of the pan.

Step 2

Sift the flour, baking powder, baking soda and salt with 1 cup granulated sugar. Mix the dry ingredients on low speed for 30 seconds to distribute the leavening. With the mixer on low speed, add half the sour cream and toss in the butter a tablespoon at a time.

Step 3

Scrape the sides and bottom of the bowl. With the mixer running on low speed, add the remaining sour cream and vanilla.

Step 4

Increase the speed to medium and beat about 3-4 minutes until the batter lightens in texture and becomes aerated. If your using a hand mixer this may take an extra minute or two. Scrape the sides and bottom of the bowl to make sure there are no pockets of unmixed batter.

Step 5

In another bowl, whip the egg whites on medium high until they form soft peaks. Turn the mixer to medium low and slowly add the other 1/2 cup sugar. Turn the mixer to medium and whip the whites to full peak.

Step 6

Fold the whites into the base in 3 parts, folding just until there are no streaks of egg white. Divide the batter evenly between the 2 pans and spread so it's level.

Step 7

Bake 25-30 minutes until the center of the cake springs back when lightly pressed or a toothpick inserted into the middle of the cake comes out clean.

Step 8

Cool at least 20 minutes in the pan and then turn out onto a cooling rack.

Step 9

Trim the brown edges off the cake, split each cake into two layers

Step 10

Fill and ice with vanilla Italian Meringue Buttercream or your favorite icing.