Mixed-Up cake recipe instructions
I'm not 100% sure that it can be saved ... but that doesn't mean that it won't end up being something good as-is.  Unless that's your only dish the size you need, I'd just throw it in the oven as-is, and see what happens.  

As it's a crust, you might look to see if you have anything that you can use for crumbs (cookies, graham crackers, ground nuts, I've even had ones made with boxed cereal and brown sugar) and make a quick crumb crust.  

You could also flip things upside down -- take whatever was intended as the filling, and add a streusel / crumble topping ... or some other buckle, betty, etc. type thing where the crust-like layer is on the top.

As you might not have time to start again, it's possible the crust might come out like a giant cookie ... if so, pop it out of the pan to let it cool while you bake the filling, then crumble it up on top of the dessert once it's out of the oven.