Preheat oven to 450 degrees F. Grease a baking sheet; set aside. Using a sharp knife, cut a pocket horizontally into each French bread slice, cutting from the top crust almost to the bottom crust.
In a small bowl stir together banana and cream cheese. Spoon 1 rounded tablespoon of the banana-cream cheese mixture into each pocket.
In a shallow bowl beat together eggs, milk, and vanilla. In a pie plate stir together peanuts, sugar, and cinnamon. Dip the stuffed bread slices into the egg mixture, turning to coat. Dip into the nut mixture, turning to coat.
Place the stuffed bread slices on the prepared baking sheet. Bake about 6 minutes or until golden brown. Turn slices over. Bake about 5 minutes more or until golden brown. If desired, serve with maple-flavor syrup and/or sprinkle with powdered sugar.