1 c. flour
1 tsp. baking powder
1 med. onion, finely chopped
1 tsp. salt
3 eggs, beaten
1 c. milk
2 pkg. frozen chopped spinach
8 oz. shredded white cheddar cheese
8 oz. shredded yellow cheddar cheese

Preheat oven to 350 degrees. Put 3 tablespoons butter in a 13 x 9 inch pan and put it in the oven to melt the butter. Mix all the ingredients together with a wooden spoon. When the butter is melted, pour mixture over the butter and return the pan to the oven.

Bake at 350 degrees for 30 to 35 minutes. Cool 20 minutes before cutting into squares. May be served hot or cool.