Mashed Potato Frittata

8 eggs
3 cups mashed potatoes
2 bell peppers, chopped fine
1 cup onion, chopped fine
1 1/2 cups mushrooms, sliced
1/2 cup parmesan cheese, grated
4 tablespoons oil

Preheat oven to 325 degrees F. In a large oven-safe skillet at medium-low heat, sauté the peppers, onion and mushrooms until the vegetables are tender, stirring often.

In a large bowl, whisk together the eggs, potatoes and cheese. Stir in vegetables from the skillet into this mixture. In the same skillet (no need to clean first), heat 2 more tablespoons of oil (raise temperature to about medium). Pour the egg mixture into the skillet. Cook on stove top only until bottom is set. Carefully, transfer the skillet to the preheated oven. Bake for about 20 minutes until the frittata is fully set. To serve, cut in wedges.