01 -
Preheat oven to 350°F and position the rack so the pan will sit in the center.
02 -
Thoroughly wash and dry all mixing equipment to remove any grease, as it can prevent adequate egg white aeration.
03 -
Sift powdered sugar, flour, and cocoa powder together three times for a light, even mixture. Set aside.
04 -
Place egg whites, cream of tartar, vanilla extract, and salt into a clean mixing bowl.
05 -
Beat on high speed until soft peaks begin to form.
06 -
With mixer running, slowly stream in the granulated sugar until stiff peaks form.
07 -
Gently fold in sifted flour mixture a 1/2 cup at a time, taking care not to deflate the batter.
08 -
Transfer batter into an ungreased 10-inch two-piece tube pan. Smooth the surface by running a thin knife around the pan to release air pockets.
09 -
Bake in the center rack at 350°F for approximately 35 minutes, or until the cake springs back lightly to the touch.
10 -
Immediately invert the hot pan onto a wire rack and cool completely while upside down. Do not unmold during this time.
11 -
Once cool, use a sharp knife to loosen the cake from the sides and center tube, then remove from the pan.
12 -
Cut with a serrated knife and serve slices with fresh fruit and whipped cream if desired.