Toss apples with white sugar and 1/3rd cinnamon to coat.
Oil the bottom of dutch oven(s)
Pour apple mix into a dutch oven(s)
Mix brown sugar, oats, flour, and rest of cinnamon in a separate bowl. Use two forks to mash the cold butter into the oats until it resembles coarse crumbs. Spread over the apples to the edges. Pat the topping gently until even. Bake until golden brown and bubbly. About 30-40 minutes.
Top with whipped cream.