In a shallow bowl, whisk together the eggs, milk, vanilla extract, and ground cinnamon until well combined.
Slice each piece of thick bread into three long sticks to create the French toast sticks.
Heat a non-stick skillet over medium heat and add a tablespoon of butter.
Dip each bread stick into the egg mixture, ensuring they are completely coated on all sides. Let any excess drip off.
Place the coated bread sticks in the skillet. Cook for about 2-3 minutes on each side, or until golden brown and crispy. You may need to do this in batches.
In a small bowl, combine the sugar and remaining ground cinnamon.
Once the sticks are cooked, immediately toss them in the cinnamon sugar mixture until well covered.
Remove from the skillet and serve warm with a side of maple syrup or honey for dipping.