Heat oven to 375ºF. Stir boiling water into cornmeal in 3 quart bowl; continue stirring until smooth. Blend in margarine and egg yolks. Stir in milk, cottage cheese, salt, baking powder, the spices, corn, cheese and onion. Beat egg whites until soft peaks form; fold into batter. Pour into greased 2 quart casserole. Bake until knife inserted near the center comes out clean, 45 to 50 minutes. 9 to 12 servings.