Ingredients
Equipment
Method
Preheat and grease
- Preheat your oven to 350°F and grease a 9x13-inch baking dish so the crisp releases easily.
Make the rhubarb filling
- Combine fresh rhubarb, sugar, and all-purpose flour in a bowl, toss until the pieces are evenly coated, then spread the mixture into the prepared baking dish.
Make the oat topping
- Mix all-purpose flour, brown sugar, old-fashioned oats, softened butter, and cinnamon with a fork until the mixture looks crumbly.
Assemble and bake
- Spread the oat topping evenly over the rhubarb mixture so the filling is fully covered.
Bake until bubbly and browned
- Bake for 40-45 minutes at 350°F until the topping is golden brown and the filling is bubbling around the edges.
Cool and serve
- Let the crisp cool for 10 minutes before serving warm so the syrup thickens slightly and the topping stays crisp.
Notes
Pro tip: slice rhubarb into consistent 1/2-inch pieces so everything bakes evenly and bubbles at the same time. Store covered in the refrigerator for up to 4 days; reheat in a 325°F oven just until warmed. Freezing is not recommended because the rhubarb texture softens after thawing. For a lower-sugar option, replace part of the sugar with an equal-measure baking sweetener blend and add a teaspoon less topping cinnamon if needed for balance.