Heat oven to 425'F. Combine soup, 2 tablespoons cheese, and sherry; stir until smooth. Spoon mashed potatoes into 1.5 quart casserole coated with cooking spray. Sprinkle SPAM on top of potatoes. Spread soup mixture over SPAM. Sprinle remaining 2 tablespoons cheese and paprika over soup mixture. Bake 20 minutes or until thoroughly heated.