Let the egg whites rest at room temperature for 30 minutes before using.
Preheat the oven to 350°F. Sift powdered sugar and flour together at least twice. Put the mixture back into the sifter and set aside on a plate.
Combine the egg whites, cream of tartar, and vanilla in a bowl. Using an electric mixer, whip on high speed until soft peaks form. Gradually add the granulated sugar about 3 tablespoons at a time. Continue beating until stiff (but not dry) peaks form.
Sift about 1/3 of flour mixture over the egg whites and gently fold in, always moving in the same direction so you don’t break the egg whites. Repeat two more times until flour mixture is completely folded in, taking care to not overwork the batter.
Spray a Bundt pan with nonstick cooking spray and pour the batter into the pan. Bake on lowest rack of oven for approximately 45 minutes, or until the top springs back when lightly touched or a toothpick inserted in the center comes out clean.
Once out of the oven, immediately flip the pan over onto a cooling rack above a cookie sheet. Let it cool to room temperature. Flip the pan back over, loosen the sides of the cake, and turn it out onto the cooling rack. Cool completely before slicing.
|
