Apple Cinnamon Roll Casserole

Lightly grease a 9x13-inch baking dish. Set aside packaged icing.

Cut each cinnamon roll into 1-inch pieces; add pieces to the prepared dish. Dollop apple pie filling randomly among cinnamon roll pieces and pour heavy cream evenly over the top.

Cover and refrigerate casserole for at least 4 hours or overnight.

Preheat the oven to 350 degrees F (180 degrees C).

Place flour, brown sugar, butter, oats, and 1 1/2 teaspoons cinnamon in a medium bowl; use a pastry cutter or a fork to mix until large crumbs form and streusel is well combined. Remove casserole from the refrigerator, uncover, and spread streusel evenly over the top.

Bake in the preheated oven until browned and bubbly, about 45 minutes.

Meanwhile, whisk packaged icing and remaining 1/2 teaspoon cinnamon together in a small bowl until blended.

Drizzle cinnamon icing over warm casserole.