Ingredients
1/2 pound (2 sticks) unsalted butter, at room temperature
2 cups granulated sugar
5 large eggs, at room temperature
3 cups all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon baking soda
1 teaspoon salt
3/4 cup plain yogurt, at room temperature
1 teaspoon pure vanilla extract
Directions
Preheat the oven to 350 degrees F. Grease and flour 9 x 13 cake pan.
Cream the butter and granulated sugar in the bowl with the an electric mixer for about 5 minutes, or until light and fluffy.
With the mixer on medium speed, beat in the eggs, 1 at a time.
In a large bowl, sift together the flour, baking powder, baking soda, and salt.
In another bowl, combine the yogurt and vanilla.
Add the flour and yogurt mixtures alternately to the batter, beginning and ending with the flour.
Pour the batter in the pan, smooth the top, and bake for 30 to 40 minutes, until a cake tester comes out clean.
When the cake is done, let it cool for 10 minutes. Take it out of the pan, place it on a baking rack and allow it to cool completely.