Preheat oven to 375 degrees and spray two ramekins with non-stick spray.
To prepare the crumble topping, combine oats, flour, brown sugar and cinnamon in a bowl. Stir to combine. Cut in butter with a fork and place in the freezer for 10-20 minutes.
While the crumble is in the freezer, prepare the filling. Add all of the ingredients to a bowl and stir to coat apples evenly. Split filling evenly between the two ramekins.
Remove crumble topping from the freezer and break apart with a fork until desired crumble texture is achieved. Split crumble topping between both ramekins. Place ramekins on a baking sheet and place in the oven. Bake for 25-30 minutes, or until golden on top.
Remove from the oven and allow to cool for 5 minutes.
Top each ramekin with a scoop of ice cream and serve.