Heat oven to 350°F; spray a 9x13-inch dish.
Layer half the waffles, chicken, and 1 cup cheese in dish.
Whisk eggs, milk, syrup, salt, and pepper in a large bowl.
Pour eggs evenly over filling; top with remaining waffles and cheese.
Cover with foil and bake 30 minutes; uncover and bake 15 minutes until golden and set.
Cool 10 minutes; drizzle with optional syrup. To freeze, cool completely, wrap tightly in plastic and foil, and freeze up to 3 months. Thaw refrigerated overnight; reheat at 350°F for 25-30 minutes.