1lb or 21oz pie filling of your choice
1 c flour
1 c packed brown sugar
1 c old fashioned oats
1 t cinnamon
1 t salt
12 T room temperature diced unsalted butter
Preheat oven at 350 degrees. Pour in pie filling in the bottom of a 9x13 pan and spread evenly. Cut the remaining ingredients with a pastry cutter to make crumbles to sprinkle on pie filling. Bake for 35 minutesish.
Mels Kitchen Cafe with some tweaks from Ash