- Preheat oven to 350°F. Butter bottom of a 13 x 9-inch baking dish; set aside.
- Coat bottom of a large skillet cook with vegetable oil and cook spinach over low heat until wilted. If desired, using kitchen shears cut spinach. Drain spinach and set aside.
- In large bowl, beat eggs, stir in milk. Stir in flour and baking powder until well blended. Stir in cheese, spinach and onion. Spoon egg mixture into baking dish.
- Bake 35 minutes or until center is set. Cool 30 minutes; cut into 6 rows by 4 rows. Serve immediately.
