This Apple Pie French Toast Casserole is a delightful breakfast or brunch dish that combines the comforting flavors of apple pie with rich, custardy French toast. Cubed French bread is soaked in a cinnamon-spiced egg mixture, layered with sweet apple pie filling, topped with a buttery oat streusel, and baked until golden and bubbly. Finished with a drizzle of caramel sauce for extra indulgence, this casserole is perfect for feeding a crowd or prepping ahead for an easy morning treat.