Coffee Sponge Cake
["1 Tbsp. instant coffee", "2 c. flour", "3 tsp. baking powder", "1/2 tsp. salt", "6 eggs", "1/2 tsp. cream of tartar", "2 c. sugar", "1 tsp. vanilla"]
["Dissolve coffee in 1 cup boiling water.", "Separate the eggs. Beat yolks.", "Add 1 1/2 cups sugar.", "To this, add alternately the dry ingredients and coffee. Beat whites until stiff.", "Add cream of tartar.", "Fold into batter the vanilla.", "Bake in ungreased pan (angel food is best) at 350\u00b0 for 60 to 70 minutes."]
["instant coffee", "flour", "baking powder", "salt", "eggs", "cream of tartar", "sugar", "vanilla"]