Potato Puff(Meal-In-One)  
["2 1/2 c. leftover mashed potatoes", "1 (10 oz.) pkg. frozen chopped spinach", "4 Tbsp. butter, melted", "1/2 tsp. salt", "1/4 tsp. pepper", "4 eggs, separated"]
["Thaw and drain spinach.", "Separate eggs.", "Combine mashed potatoes, spinach, butter, seasonings and 4 egg yolks.", "Beat 4 egg whites until stiff and fold gently into vegetable mixture. Gently place in a 1 1/2-quart oven casserole.", "Bake at 375\u00b0 for 30 to 40 minutes until puffed and golden.", "Serves 6."]
["leftover mashed potatoes", "spinach", "butter", "salt", "pepper", "eggs"]