Spinach Bars
["4 Tbsp. butter", "3 eggs", "1 c. flour", "1 c. milk", "1 tsp. salt", "1 tsp. baking soda", "1 lb. Cheddar cheese, grated", "1 (10 oz.) pkg. chopped spinach, thawed and dried", "1 small onion"]
["In a 9 x 13-inch pan, melt butter.", "Mix remaining ingredients and spoon into a pan.", "Bake at 350\u00b0 for 35 minutes.", "Cool slightly before cutting.", "Serve hot or at room temperature."]
["butter", "eggs", "flour", "milk", "salt", "baking soda", "Cheddar cheese", "chopped spinach", "onion"]