Spray a 9x13 baking dish with cooking spray. Slice french bread into bite-sized cubes. Place in the bottom of the pan.
Whisk eggs, milk, vanilla, granulated sugar, and cinnamon until blended. Pour over bread pieces in pan. Cover with plastic wrap and refrigerate for at least 6 hours or overnight.
Preheat oven to 350°F.
Remove french toast from the refrigerator. Evenly spread pie filling over the top.
With a hand or a stand mixer, combine butter, flour, brown sugar, and oats until a crumble forms. It’ll take awhile, especially with a hand mixer. Sprinkle evenly over the top of the casserole.
Bake for 33-38 minutes until slightly golden and baked through. Serve warm with powdered sugar, syrup and/or whipped cream.