Easy Rhubarb Crisp Recipe with Oat Topping
This easy rhubarb crisp recipe is seriously one of the best sweet and tangy treats for spring and early summer – and it’s SO easy to make. You can use fresh or frozen rhubarb, so it’s super flexible, and the buttery oat crumble on top? Perfection. It’s that old school rhubarb crisp everyone loves, and honestly, it’s ridiculously easy to throw together. If you’re hunting for a homemade dessert that hits that ideal tart sweet combo, this one’s going to be your new go to.
There’s something undeniably comforting about rhubarb crisp. The rhubarb turns all soft and jammy underneath, and the oat topping gets golden and buttery and so crisp. It’s the kind of dessert that feels like a hug from your grandma (if your grandma also was the foundation of your rhubarb dessert obsession like mine was) and tastes like summer in every bite.
If you love baking with rhubarb, you’ll also want to try my rhubarb muffins, strawberry rhubarb freezer jam, and this nostalgic rhubarb custard dessert (my all time favorite). Rhubarb season is short, so I like to make the most of it.
Why You’ll Love This Rhubarb Crisp
- Easy one-pan dessert
- Perfect for fresh OR frozen rhubarb
- Buttery oat crumble topping
- Sweet and tart flavor balance
- Classic old fashioned rhubarb crisp
- No mixer required
- Ready in under an hour
Ingredients for Rhubarb Crisp
For the Filling
- 4 cups chopped rhubarb (fresh or frozen, cut into ½-inch pieces)
- ¾ cup granulated sugar (adjust based on tartness)
- 1 tablespoon cornstarch
- 1 teaspoon vanilla extract
For the Oat Crisp Topping
- 1 cup rolled oats
- ¾ cup all-purpose flour
- ½ cup brown sugar
- ½ teaspoon cinnamon
- ¼ teaspoon salt
- ½ cup unsalted butter, melted
How to Make Rhubarb Crisp
- Preheat your oven to 375°F (190°C). Lightly grease a 9×9-inch baking dish (or similar).
- Make the filling: In a large bowl, combine rhubarb, sugar, cornstarch, and vanilla. Toss until evenly coated, then spread it evenly in the prepared baking dish.
- Mix the topping: In a separate bowl, stir together oats, flour, brown sugar, cinnamon, and salt. Drizzle in the melted butter and mix until crumbly.
- Assemble: Sprinkle the topping evenly over the rhubarb mixture.
- Bake: Place in the oven and bake for 40–45 minutes, or until the filling is bubbly and the topping is golden brown.
- Cool slightly: Let it sit for 10–15 minutes before serving—it helps the filling set a bit.
Can I Use Frozen Rhubarb?
Yes! Frozen rhubarb works perfectly in this rhubarb crisp recipe. There’s no need to thaw it first. Simply add it directly to the filling.
If using frozen rhubarb, you may want to add an extra ½ tablespoon of cornstarch to help thicken the filling since frozen fruit releases more liquid.
Make Strawberry Rhubarb Crisp
For a classic strawberry rhubarb crisp, replace half the rhubarb with sliced strawberries. This adds natural sweetness and softens the tart flavor.
Try:
- 2 cups rhubarb
- 2 cups strawberries
This combination is also delicious in my strawberry rhubarb freezer jam and makes a perfect summer dessert.
Tips for the Best Rhubarb Crisp
- Add strawberries for a classic combo: See above for my suggestion on this alternation!
- Make it gluten-free by using almond flour or a GF flour blend.
- Brighten that color with a bit of Jell-O: This is one of my grandma’s tricks – sprinkle in a bit of strawberry jell-o powder after you’ve chopped your rhubarb and it’ll give it an extra pop of color and sweetness.
- Serving suggestion: Warm with a scoop of vanilla ice cream or a dollop of whipped cream. (Trust me on this one.)
- For a crunchier topping: Bake uncovered the entire time
- For a softer topping: Lossing cover with foil halfway through baking.
How to Store Rhubarb Crisp
- Refrigerator: Store covered in the refrigerator for up to 4 days.
- Reheat: Warm in the oven at 325°F until heated through, or microwave individual portions.
- Freeze: Rhubarb crisp can be frozen after baking. Let cool completely, then freeze tightly covered for up to 3 months.
Serving Ideas
This rhubarb crisp is always delicious, but I like it best served warm. Try it with:
- Vanilla ice cream
- Whipped cream
- Heavy cream drizzle
- Vanilla yogurt
- Custard sauce
It also makes a great brunch dessert or summer potluck dish.
More Rhubarb Recipes to Try
If you’re enjoying rhubarb season, here are more favorites:
- Rhubarb Muffins
- Rhubarb Custard Dessert
- Strawberry Rhubarb Freezer Jam
- Rhubarb Simple Syrup
- Rhubarb Slush
These are all great ways to use fresh rhubarb while it’s in season.
The Best Old Fashioned Rhubarb Crisp
To me, this rhubarb crisp is more than just a dessert—it’s a celebration of summer, of simple pleasures, and of recipes that don’t require a stand mixer or a pastry degree to taste like home.
This homemade rhubarb crisp is everything you want in a simple summer dessert. It’s sweet, tart, buttery, and incredibly easy to make. Whether you’re using rhubarb from your garden or grabbing a bundle from the store, this easy rhubarb crisp recipe is always a hit.
Bake it for a picnic, potluck, or just a cozy summer night at home. Once you try it, you’ll understand why this old fashioned rhubarb crisp is a classic that never goes out of style.
Happy baking!
Rhubarb Crisp
Ingredients
Filling
- 4 cups chopped rhubarb
- 3/4 cup sugar
- 1 tbsp cornstarch
- 1 tsp vanilla extract
Topping
- 1 cup rolled oats
- 3/4 cup flour
- 1/2 cup brown sugar
- 1/2 tsp cinnamon
- 1/4 tsp salt
- 1/2 cup unsalted butter melted
Instructions
- Preheat oven to 375 °F
- Grease a 9×9 in baking dish
- Combine rhubarb, sugar, cornstarch and vanilla. Toss until coated and then spread into baking dish.
- In a separate bowl, mix oats, flour, brown sugar, cinnamon and salt. Drizzle in butter and mix until crumbly.
- Sprinkle topping over rhubarb mixture.
- Bake for 40-45 minutes until filling is bubbly and topping is golden brown.
- Allow to cool 10-15 minutes before serving for the filling to set up.
- Enjoy!
