Preheat the waffle baker and grease it with cooking spray.
In a large bowl, stir together the leftover stuffing and eggs. Add 1/4 cup of chicken broth and mix until well combined. Continue adding chicken broth as needed until the mixture is well-moistened.
Scoop half of the stuffing mixture into the prepared waffle baker, spreading it evenly. (The stuffing will not spread or expand like regular waffle batter as it bakes, so it's important to arrange it in an even, thin layer.) Close the lid and let the waffle bake until golden brown and the egg is cooked throughout.
Transfer the waffle to a serving plate then repeat the filling and baking process with the remaining stuffing. Serve the waffles with leftover cranberry sauce and warm leftover gravy.