1/4 tsp. oregano
1 (16 oz.) can tomatoes pureed
1 1/2 c. water
1 box au gratin potatoes
8 oz. shredded Mozzarella cheese
Pepperoni, sliced

Mix oregano, water and tomatoes in pan and bring to a boil. Line baking dish with potatoes and dry au gratin mixture; add tomato mixture and top with pepperoni and Mozzarella cheese. Bake at 400 degrees for 35 minutes.