Prepare a batter similar to apple cake: beat eggs with sugar and vanilla, stir in melted butter. Add flour, baking powder, salt and cinnamon to form a thick batter. Fold in plenty of diced apples (and nuts if using). Spread in a rectangular pan. Bake at 350?F until bars are golden and a toothpick comes out clean (about 25?30 min). Drizzle with a simple brown sugar glaze or frosting if desired. Cut into bars..