01 -
Preheat oven to 190°C. Lightly grease a 20 x 20 cm or 23 x 23 cm baking pan.
02 -
In a large bowl, combine rhubarb, granulated sugar, and corn starch (use half the starch if rhubarb is fresh). Transfer mixture evenly into the prepared baking pan.
03 -
In a separate bowl, blend together butter, brown sugar, rolled oats, and flour. Use a pastry cutter, fork, or fingertips to form coarse crumbs. Evenly distribute topping over rhubarb filling and gently press without compacting.
04 -
Place pan in the oven. Bake for 35–40 minutes until topping is golden and filling is bubbling at the edges.
05 -
Allow crisp to rest for a minimum of 10 minutes before serving, ideally accompanied by ice cream.