3 tbsp. olive oil
1 lg. onion, chopped
1 red bell pepper, chopped
1 c. sliced fresh mushrooms
12 eggs
3 oz. pepperoni, sliced very thin and chopped
1/2 c. milk
1/2 tsp. black pepper

Preheat oven to 350 degrees. In 10 inch cast-iron skillet, heat oil over medium-high heat. Add onion, red pepper and mushrooms; cook, stirring occasionally, 7 to 8 minutes until vegetables are tender. In large bowl, whisk together eggs, pepperoni, milk and black pepper.

Pour over vegetables in skillet. Place skillet in oven; bake 15 to 20 minutes until egg mixture is set. Use a spatula to slide the frittata onto large serving platter. Cut into wedges, serve warm. Serves 8.