Preheat the oven to 375F/190C and grease two small ramekins with butter.

Peel, core and chop with apples into small chunks. Evenly divide the apple chunks between the two ramekins.

In a small bowl, stir together the flour and sugar. Rub in the butter with your fingertips until you've got a breadcrumb-like consistency. Evenly sprinkle the crumble topping on the apple chunks.

Place the apple crumbles into the preheated oven and cook for 30 minutes, until the apples are soft and the top is golden.