The night before, melt butter in small pan over medium heat. Stir in brown sugar and corn syrup until well blended. Spread into a 9X13 baking pan. Spread apple slices over sugar mixture evenly. Arrange french bread over apple slices.
In medium bowl, beat eggs until light nd beat in milk and vanilla. Pour egg mixture over bread. Cover and refrigerate overnight.
In morning, preheat oven to 350 degrees. Bake uncovered for 40 minutes or until bread is golden.