01 -
Preheat your oven to 400°F and lightly butter a 2-quart casserole dish. This creates the perfect non-stick base for your crisp.
02 -
In a large mixing bowl, gently combine your sliced rhubarb with cornstarch, sugar, and cinnamon until everything is well coated. Spread this mixture evenly across your prepared baking dish.
03 -
Mix together oats, flour, sugar, cinnamon, and salt in another large bowl. Add your cold butter pieces and work them in with your fingers or a pastry cutter until you get a crumbly texture that looks like chunky cookie dough.
04 -
Sprinkle your crumble topping evenly over the rhubarb filling. Pop it in the oven for about 35 minutes until the top is beautifully golden and you can see the filling bubbling around the edges. Let it rest for 10 minutes before serving - trust me, it's worth the wait!