Instructions
- Preheat oven to 375°F (190°C). Butter and flour a 6-cup soufflé dish.
- Melt Butter from the Base group in a saucepan over medium heat. Whisk in Flour and cook for 1-2 minutes to make a roux.
- Gradually whisk in Milk from the Base group until smooth. Bring to a simmer, stirring constantly. Cook for 5-7 minutes, or until thickened. Season with Nutmeg, Salt, and Pepper.
- In a large bowl, combine Spinach, Cheddar Cheese, Parmesan Cheese, Cream Cheese, and Egg Yolks from the Filling group. Stir well.
- Stir the cheese and spinach mixture into the white sauce (Base).
- In a clean, dry bowl, beat Egg Whites from the Egg Whites group with Cream of Tartar until stiff peaks form.
- Gently fold one-third of the beaten egg whites into the cheese mixture to lighten it. Then, gently fold in the remaining egg whites until just combined. Do not overmix.
- Pour the mixture into the prepared soufflé dish. Bake for 30-35 minutes, or until puffed and golden brown. Serve immediately.
