Cheddar Potato Casserole
["3 c. mashed potatoes (season with salt and pepper)", "4 eggs, separated", "1 c. shredded Cheddar or American cheese", "1 Tbsp. finely chopped onion", "1/2 green pepper, finely diced", "1/2 tsp. celery salt", "salt to taste", "paprika"]
["Bring potatoes to room temperature.", "If leftover, cold.", "Beat egg yolks into potatoes until well mixed.", "Stir in cheese, onion, pepper and seasonings.", "Whip egg whites to soft peaks.", "Fold into potatoes.", "Spoon into well buttered casserole (1 1/2-quart). Sprinkle with paprika.", "Bake at 375\u00b0 for 25 to 30 minutes."]
["potatoes", "eggs", "cheese", "onion", "green pepper", "celery salt", "salt", "paprika"]