Preheat your waffle iron according to the manufacturer's instructions.

In a mixing bowl, whisk together the eggs, milk, vanilla extract, sugar, and ground cinnamon until smooth.

Take a slice of bread and dip it into the egg mixture, coating both sides evenly.

Lightly grease the waffle iron with butter to prevent sticking.

Place the dipped bread in the hot waffle iron and close the lid. Cook until golden brown, usually about 3-5 minutes.

Open the waffle iron carefully to check if the waffles are golden. If they need more time, close and cook for an additional minute.

Continue with the remaining slices of bread, greasing the iron as needed.

Serve the waffles warm with your favorite toppings.