Preheat the oven to 375 degrees F. Spray a 9x13-inch baking dish with non-stick cooking spray and set aside.
Remove icing from cinnamon rolls tubes and set aside. We'll be using that later.
Cut each cinnamon roll into 4 pieces. Evenly layer cinnamon roll pieces into the bottom of the prepared baking dish.
Melt butter and pour over the cinnamon roll pieces.
Mix the brown sugar and cinnamon in a separate bowl then sprinkle over the top of the buttered cinnamon roll pieces like a crumble.
Cut up apples in the filling. I just usually take a knife and cut the apples while they're in the can. It makes it easier to dice and creates less mess.
Add the diced apples and filling over top of the crumble, then the pecan halves.
Use a spoon to mix the pecans into the casserole a bit to incorporate.
Bake for 40 minutes, covered then uncovered for another 3-5 minutes or until golden brown on top. (Be careful while browning because pecans can burn quickly when on top)
Place all the icing that was set aside earlier into a microwave safe bowl and melt slightly for 10 seconds. It just needs to be soft enough to pour.
Drizzle the warm icing over the casserole and serve warm!
Notes
If you are not a fan of pecans you can use walnuts or just leave them out altogether.
Use any of your favorite filling, see my tips above.
If you find apple pie filling too sweet, add a a squeeze of lemon juice to the filling to cut the sweetness.