Caramel Apple Crumble Pie

unsalted butter, melted (half of one stick)

large egg

granulated sugar

light brown sugar, loosely measured

vanilla extract

cinnamon

allspice

ground cloves

salt, optional and to taste

all-purpose flour

whole rolled old-fashioned oats (not quick cook or instant)

apple pie filling (I used Comstock More Fruit Cinnamon 'n Spice Apple filling)

9-inch frozen pie crust (or make your own using your favorite recipe)

caramel sauce, caramel ice cream topping. Dark Rum Caramel Sauce or Vanilla Caramel Glaze, optional but recommended for drizzling

ice cream or whipped topping, optional