How can I use left over crumble topping? I like making fruit crumbles, and I like fruit crumbles, but I have a problem...

I always make the crumble topping by estimating quantities, adjusting the ingredients until I get the consistency I want. This always leaves me with a lot of crumble left over when the fruit is covered.

What can I do with this excess crumble topping? Obviously it’s a nice treat on its own, and I could cook more fruit, but is there another recipe I could use this for?

(I wonder if there’s a way to convert it into a shortbread, but I don’t know how to go about it.)
I'd bake the left overs on a baking sheet and freeze the result in zip bags.

It will keep longer.