1 lg. onion, chopped
1 (4 oz.) can pieces and stems mushrooms, drained
1 tbsp. oil
1 (10 oz.) pkg. frozen chopped spinach, thawed and pressed dry
5 eggs, beaten
3 c. (12 oz.) shredded Muenster or Monterey Jack cheese
1/4 tsp. salt
1/8 tsp. pepper

Saute onion and mushrooms in oil in a large skillet until tender. Add spinach, and cook until excess moisture evaporates; cool.

Combine eggs, cheese, salt and pepper; stir into spinach mixture. Pour into a greased 9-inch pie plate. Bake at 350 degrees for 30 minutes or until set.