Heat oven to 400 degrees. Heat 1 1/3 cups water and 1/4 teaspoon salt to boiling. Remove from heat. Stir in 1 1/3 cups instant mashed potato mix (dry). Stir in 1/2 cup dairy sour cream. Turn into ungreased 1-quart casserole. If desired, sprinkle with paprika, snipped chives or snipped parsley. Bake uncovered 10 minutes. Makes 4 servings.