Joanne'S Spinach Squares
["3 Tbsp. butter", "3 eggs", "1 c. milk", "1 c. flour", "1 tsp. baking powder", "1 tsp. salt", "1 lb. sharp Cheddar cheese", "1 pkg. frozen chopped spinach, thawed and drained", "1/2 small onion, diced"]
["Preheat oven to 350\u00b0.", "Melt butter in baking pan; remove and cool.", "Mix eggs, milk, flour, baking powder and salt well.", "Add spinach, cheese and onion and mix well.", "Put in pan and bake for 40 minutes.", "Let stand 15 minutes before cutting.", "Freezes well."]
["butter", "eggs", "milk", "flour", "baking powder", "salt", "Cheddar cheese", "spinach", "onion"]