Place oven rack in the lowest position. Preheat oven to 350° F.
Place egg whites in a large bowl; let stand at room temperature 30 minutes. Sift 1/2 cup sugar and flour together twice; set aside.
Add cream of tartar, extracts, and salt to egg whites; beat on medium speed until soft peaks form. Gradually add remaining sugar, about 2 tablespoons at a time, beating on high until almost stiff peaks form.
Gradually fold in flour mixture, about 1/2 cup at a time.
Gently spoon into an ungreased 10-inch tube pan. Cut through batter with a knife to remove air pockets. Bake 35-40 minutes or until lightly golden brown and entire top appears dry. There may be some cracking, which is a clue the cake is done. Test by very gently pressing the top of the cake; it should spring back.
Immediately invert pan; cool completely, about 1 hour.
Run a knife around side and center tube of pan. Remove cake to a serving plate. Yield: 12-16 servings.
If making in baby angel food cake pans, as shown above, this will yield about eight cakes, depending on how full they are filled and the size of the pans. Bake for about 20 minutes.
Keywords: Cake, cake flour, Desserts, egg yolks, Eggs, Family Recipe, flour, Frugal Hausfrau, mock mascarpone, Strawberries