Potato Pizza

3 cups potatoes, mashed (prepared with milk)

1 egg beaten

1/4 cup parmesan cheese, grated

2 tablespoons butter or margarine, melted

1 teaspoon salt

1 can (8 ounces) pizza sauce

3 ounces pepperoni, sliced

3 ounces pork sausage

4 fresh mushrooms, sliced

1 cup Mozzarella cheese, shredded

1/4 cup Cheddar cheese, grated

In a bowl, combine potatoes, egg, Parmesan cheese, butter or margarine and salt. Press onto bottom and up the sides of a greased 11x7x2 inch baking dish. Spread pizza sauce over potato mixture to within 1/2 inch of edges. Top with pepperoni, sausage and mushrooms. Sprinkle with Mozzarella and Cheddar cheese. Bake at 400 degrees for 25 to 30 minutes or until heated through and cheese is melted. 

recipe source here