KELLY’S NOTES: All leftover mashed potatoes will vary in consistency depending on how much cream, milk or melted butter you added to the original batch. If the waffle batter looks too dry and isn’t holding together, add one more egg. If it looks too wet, add more flour, 1 tablespoon at a time, until the mixture is cohesive. Do not lift up the waffle baker lid too soon or you’ll risk having the mixture separate and stick to the waffle baker. Allowing the waffle to cook through before opening the waffle baker ensures the waffle can be removed whole.