Grease a 9x9 or 2.5-quart baking pan, with non-stick spray. Arrange the bread cubes into the pan.
Pour evenly over bread cubes. Press the bread cubes slightly down to absorb the milk/egg mixture. Cover the baking dish tightly with plastic wrap or foil and store in the fridge for four hours. (You can bake this immediately as well too but the toast may not soak up as much of the flavor.)
When you are ready to bake
Remove the dish from refrigerator and uncover. Preheat oven to 350 degrees F.
Place an even layer of the sliced apples over the cubed bread.
Make the streusel topping
In a medium bowl, combine the flour, brown sugar, salt, and cinnamon together. Mix in the oats and pecans. Cut in the cubed butter with a pastry blender or two forks. Sprinkle the streusel topping evenly on top. Add a few more slices of apples. Drizzle an even layer of caramel sauce on top.
Drizzle with caramel sauce before serving, if desired and enjoy.
Reheating your Apple French Toast Casserole is easy and ensures you can enjoy its deliciousness once again. Here's how to do it:
1. Oven Method:
2. Microwave Method (for individual servings):