Preheat your oven to 350°F (175°C). Make sure your tube pan (10-inch) is clean and dry; do not grease it.
Sift together the cake flour and 1/2 cup of the granulated sugar. Set aside.
In a large mixing bowl, beat the egg whites, cream of tartar, and salt on medium speed until frothy. Gradually add the remaining 1 cup of sugar, about 2 tablespoons at a time, beating continuously until stiff peaks form.
Gently fold in the vanilla extract and almond extract, if using.
Sift the flour mixture over the beaten egg whites, about 1/4 cup at a time, and gently fold in with a spatula. Be careful not to deflate the egg whites.
Pour the batter into the tube pan, spreading it evenly. Run a knife through the batter to eliminate any large air bubbles.
Bake for 35-40 minutes or until the cake is golden brown and springs back when lightly touched.
Invert the pan immediately onto a bottle or metal funnel to cool completely. This prevents the cake from collapsing.
Once cooled, run a knife around the edges of the pan to loosen the cake and remove it.
Slice and serve plain or with fresh berries, whipped cream, or a dusting of powdered sugar.