Preheat oven to 350°F.
Melt butter in 10½-inch oven-proof skillet over medium heat. Add ground red pepper and onions. Sauté onions until soft.
Stir in red bell pepper and garlic; sauté for an additional 1 to 2 minutes. Remove from heat.
Beat eggs, herbs, salt and Parmesan cheese together. Pour egg mixture over sautéed vegetables.
Sprinkle mozzarella or Cheddar cheese over the top. Place pan in oven.
Bake for 15 minutes.
Slide frittata onto a plate and serve.
Use fresh rosemary and thyme for best flavor, but if using dried herbs use about one third the amount of fresh.
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