Chalmer'S Spinach Squares
["4 Tbsp. margarine", "3 eggs", "1 c. milk", "1 c. flour", "1 tsp. baking powder", "1 tsp. salt", "1 lb. Cheddar cheese", "2 pkg. frozen chopped spinach, squeezed dry", "1 Tbsp. chopped onion"]
["Preheat oven to 350\u00b0.", "Put butter in 9 x 13-inch baking dish. Melt in oven.", "Remove."]
["margarine", "eggs", "milk", "flour", "baking powder", "salt", "Cheddar cheese", "onion"]