Cheesy Mashed Potatoes

4 large baking potatos, about 2 pounds, peeled and cut
into 1-inch pieces
1 cup warm milk
2 T. butter, room temperature
4 oz shredded mozzarella cheese
4 oz shredded sharp Cheddar cheese
1/4 tsp ground black pepper
1/4 tsp salt
1/4 tsp paprika
dash of red pepper

Cook potatoes in boiling water until tender. Drain well. Put potatoes back in saucepan; stir over low heat until dry, about 2 minutes. Remove from heat. Mash, adding about 1/2 cup milk and butter. Add cheese and seasonings. Mix well, adding remaining milk until desired consistency is reached.