Heat the oven to 350 degrees F. Spray a 9 x 13 baking dish with non-stick cooking spray. Set aside.
Place the bread cubes into a large mixing bowl and set that aside. In a medium mixing bowl, whisk together the eggs half-and-half, milk, sugar, and vanilla unitl well combined. Pour the milk mixture over the bread and let rest for 10 minutes so the bread can soak up the liquid.
While the bread rests, add the butter to a large skillet and place over medium heat. Once melted, add apples, brown sugar, and cinnamon. Stir the apples until they are warmed through but not mushy, about 5-10 minutes.
Add the apples to the bread cubes and gently fold them all together. Then pour everything into the prepared baking dish and spead into an even layer.
Bake for 35-40 minutes or until golden brown on top. Remove from the oven and let rest for 5 minutes before serving warm.
Notes
If you want to prep this french toast the night before, follow the directions until everything is in the baking dish and ready to go. Then cover the dish with plastic wrap and refrigerate it overnight. In the morning, preheat the oven and bake as directed.