Spinach Soufflé

Thaw spinach and drain thoroughly, squeezing the excess water out. Gently sauté the onions in butter until soft; add salt, pepper, and a little lemon juice to taste. Mix together the spinach, onions, and cheese in a small (about one quart) casserole dish.

Beat the eggs until foamy; add the milk and cream of tartar and beat some more. Pour over the spinach mixture and work it in gently with a wooden spoon. Immediately place in a 350°F. oven and bake for 20 to 30 minutes.