Slice the Hawaiian rolls in half, creating two layers.
In a mixing bowl, whisk together the eggs, milk, vanilla extract, cinnamon, and sugar.
Heat a non-stick skillet or griddle over medium heat and melt 1 tablespoon of butter.
Dip each roll piece into the egg mixture, ensuring both sides are coated.
Place the dipped rolls onto the skillet and cook for 2-3 minutes per side, or until golden brown.
Repeat with the remaining rolls, adding more butter as needed.
Serve warm with maple syrup and a sprinkle of powdered sugar, if desired.