Tbl Warm Water and mix on low speed until frothy. Add, 1/2 tsp Salt, 1 tsp Cream of Tartar, 1 tsp Vanilla and beat on medium speed until soft peaks form. While on medium speed, begin adding 3/4 Cup Caster Sugar, 1 tablespoon at a time. Increase to high speed and mix until peaks are stiff and not dry.
Remove bowl from mixer and stift 1/6 of the flour/sugar into the whites and fold after each addition. Do this 6 times.
Add batter to a clean tube pan and flatten out the top. Insert a knife into the middle of the batter and run it through the batter making a circle around the tube to remove large air bubbles.
Bake for 35-40 minutes until golden brown.
Turn upside down and let cool. Remove from pan after about an hour. You can glaze this cake, eat it plain or with fresh berries. It is so good. Like my Mom always said, there is nothing like a homemade Angle Food Cake and there isn't.