In a wide shallow dish combine milk, cream, eggs, vanilla, cinnamon and scraped vanilla bean.
Spread the bread slices evenly with the peanut butter and jelly and form sandwiches.
Dip assembled sandwiches in batter, coating each side evenly.
Heat a large cast iron or non-stick griddle over medium heat. Grease pan with butter. When butter starts to sizzle, turn heat up a notch. Place sandwiches on the griddle and cook, 4 to 5 minutes on each side, until golden brown.
Cut diagonally and serve with maple syrup or dust with confectioner's sugar.