1 tablespoon butter, melted
Cooking spray
2 (6-ounce) packages fresh baby spinach
1 1/4 cups (5 ounces) shredded reduced-fat sharp cheddar cheese
3/4 cup (3 ounces) shredded Monterey Jack cheese
1 1/3 cups all-purpose flour (about 5 3/4 ounces)
1 1/2 cups fat-free milk $
1 cup egg substitute
1 teaspoon salt
1 teaspoon baking powder
2 teaspoons Dijon mustard
1/4 teaspoon freshly ground black pepper
1/8 teaspoon ground nutmeg
1/8 teaspoon ground red pepper