Spinach Squares(Appetizer)

Ingredients

• 1 c. flour
• 1 tsp. salt
• 1 tsp. baking powder
• 2 eggs, beaten
• 1 c. milk
• 1 stick melted butter or margarine
• 1/2 grated onion
• 1 (10 oz.) pkg. spinach, thawed and drained
• 1 lb. grated sharp Cheddar cheese (1/2 lb. will do)