Melt 1/2 stick of butter in 9x13 inch pan. In bowl, mix 3 large eggs, flour, milk, salt, baking powder and grated cheese. Add 10 oz. package frozen chopped spinach, thawed, but not cooked and water squeezed out.
Pour mixture over melted butter and bake in a 350 degree oven for 35 minutes. In case of leftovers, they are delicious warmed up for several nights there after.