Preheat your oven to 350°F (180°C). Grease a 9×13-inch baking dish with melted butter.
Cut each cinnamon roll into halves or quarters and arrange evenly in the dish.
In a bowl, whisk together eggs, milk, vanilla, and cinnamon until smooth.
Pour the mixture over the cinnamon rolls, ensuring all pieces are coated. Let sit for 25 minutes to soak.
Bake for 20–25 minutes until golden brown and puffed.
Let cool slightly, then drizzle icing and maple syrup on top.
Serve warm and enjoy this delicious Easy Cinnamon Roll Casserole.