Preheat the oven to 350°F and lightly grease a baking dish.
In a large bowl, whisk together the eggs, milk, vanilla, and 1/2 teaspoon cinnamon.
Add the Hawaiian rolls to the egg mixture and gently toss until each roll is coated.
Arrange the coated rolls in the prepared baking dish.
In a small bowl, combine 1 tablespoon sugar with 1/2 teaspoon cinnamon.
Sprinkle the cinnamon sugar evenly over the French toast bites. (you will not use the whole thing, sprinkle however much you want).
Bake at 350°F for about 14 minutes, or until the egg mixture is cooked through and the tops of the rolls are lightly golden.
Remove from the oven and add additional cinnamon sugar if desired.
Allow the French toast bites to cool slightly before serving. Serve plain or with maple syrup for dipping.
