This is a different spin on good old mashed potatoes that we absolutely love. A friend's father is the cook in their family and he shared this recipe with me but not the exact amounts. I made it as I thought our family would like it and it has proven to be a real comfort dish to us.
Cook potatoes and mash with milk to desired consistency. In large fry pan or heat proof baking dish melt 3 tablespoons of butter and saute 1 small chopped green pepper and 1 small chopped onion until wilted. Add to mashed potatoes and add 1/2 cup of grated cheddar and 1/2 cup of grated mozzarella. Fold all ingredients with salt and pepper to taste. Place in greased baking dish and bake at 350 for 1/2 hour.