Mix eggs, milk, vanilla, and cinnamon together in a bowl.
Heat the skillet to medium and melt butter in it.
Dip each slice of bread into the egg mixture, ensuring both sides are coated.
Place the dipped bread slices in the skillet.
Cook until the bottom is browned, then flip and cook the other side until browned.
Remove the cooked bread from the skillet.
Sprinkle with powdered sugar.
erve with maple syrup if desired.