step 1
Mix the oats and sugar together in a large bowl
step 2
Melt the butter
step 3
Add the melted butter to the oats and sugar (and cinnamon, if included) and combine thoroughly
step 4
Spread the oat crumble topping evenly over the dish to be covered e.g. Precooked fruit
step 5
Bake for 20 minutes at 190C / fan 170C / gas 5 until the crumble top is golden and the fruit is bubbling