Rhubarb crisp is a simple, one-dish dessert packed with tart, bubbling rhubarb filling and topped with a golden, buttery oat topping that bakes up perfectly crunchy. I will serve it warm with a scoop of vanilla ice cream straight from the oven, or enjoy it cold the next morning with a hot cup of coffee. Honestly, I love it both ways.
Here is why you'll love this recipe:
- Simple, pantry-friendly ingredients - no fancy equipment, no pie crust, no stress. This is old-fashioned comfort baking at its best.
- Fresh or frozen rhubarb both work - no need to thaw frozen rhubarb first, making this a year-round dessert option.
- Easily customizable - toss in a cup of chopped strawberries to mellow out the tartness and add natural sweetness to the filling.
- The perfect rhubarb introduction - if your family has never tried rhubarb, this sweet-tart crisp is the most approachable, crowd-pleasing way to win them over.
Ingredients needed:
Good news! You don't need anything fancy with my recipe. Most of these ingredients are already sitting in your pantry, and the rhubarb is the real star of the show. If you're working with frozen rhubarb, go ahead and use it straight from the freezer, no thawing needed. Just expect a few extra minutes of bake time.
Recipe Card?
To find the full printable recipe with specific measurements and directions CLICK HERE to go to the recipe card.
Substitutions
Every kitchen is a little different, and that's totally okay.
Here are some easy swaps that won't compromise your results:
| Ingredient | Substitution |
|---|---|
| Old-fashioned oats | Certified GF oats for a gluten-free topping |
| All-purpose flour (topping) | Almond flour or a 1:1 GF flour blend |
| Unsalted butter | Vegan butter (same cold cubed method) |
| Light brown sugar | Dark brown sugar (richer, more molasses flavor) or coconut sugar |
| Granulated white sugar (filling) | Raw cane sugar or reduce and add strawberries for natural sweetness |
| Cornstarch | Arrowroot powder, 1:1 swap |
| Fresh rhubarb | Frozen rhubarb, used straight from frozen - no thawing |
Gluten Free?
Swap the all-purpose flour in the topping for a 1:1 GF blend and use certified gluten-free oats. The filling is already GF since we're using cornstarch as the thickener!
Step-by-step Instructions
Making rhubarb crisp is genuinely hard to mess up but a few small techniques make the difference between a soggy topping and a perfectly golden, crunchy finish.
Follow my steps and you'll nail it every single time.
Preheat & Prep Your Dish
Preheat your oven to 375°F. Lightly grease a 9-inch baking dish with butter or non-stick spray and set it on a rimmed baking sheet.
Why use a baking sheet?
That baking sheet is your insurance policy. The rhubarb filling bubbles enthusiastically and you don't want it on the bottom of your oven.
Prep the Rhubarb
Wash your rhubarb stalks thoroughly and trim off any leaves; those go straight in the trash, not your bowl. Chop the stalks into ½"-1" pieces. Uniform pieces matter here; they'll cook at the same rate and give you an even filling.
Can I use frozen rhubarb?
Absolutely. Use it straight from the freezer, no thawing needed. You may need an extra 5-10 minutes of bake time, and the filling may release a bit more liquid, which your cornstarch will handle.
Make the Rhubarb Filling
Add the chopped rhubarb to your prepared baking dish. Sprinkle over the granulated sugar, cornstarch, lemon juice, vanilla extract, cinnamon, nutmeg, and salt. Toss everything together until the rhubarb pieces are evenly coated.
Why Cornstarch?
Cornstarch needs to reach a boil to fully activate, which is exactly why you need that center bubble before pulling the crisp from the oven. It's not just about doneness; it's the science behind a set filling.
Make the Crisp Topping
In a medium bowl, combine the flour, brown sugar, rolled oats, and salt. Add the cold cubed butter and use your fingertips to rub the butter into the dry ingredients until the mixture looks like coarse, clumpy sand.
Top the Rhubarb
Scatter the oat topping evenly over the rhubarb filling. Don't press it down, just let it sit loosely on top. That airflow is exactly what makes it crisp up in the oven rather than steam.
Bake to Golden Perfection
Bake at 375°F for 45-55 minutes, until the topping is deep golden brown and the filling is visibly bubbling in the CENTER of the dish not just around the edges.
When is it done?
That center bubble is your cue that the cornstarch has fully activated and your filling has set. Pull it early and you'll have a runny crisp. Be patient!
Rest, Then Serve
Let the crisp rest for 10-15 minutes before serving. This allows the filling to thicken up just a bit more and makes it much easier to scoop cleanly. Serve warm with vanilla ice cream or sweetened whipped cream.
What to Serve With Rhubarb Crisp
Once it's out of the oven and rested, this is where the fun starts:
- Vanilla ice cream - the classic pairing; cold and creamy against warm tart filling is unbeatable.
- Sweetened whipped cream - light and airy, lets the rhubarb flavor take center stage.
- Strawberry ice cream - doubles down on the berry vibe, especially if you added strawberries to the filling.
- Vanilla custard or crème anglaise - the classic British way to serve a crisp, and honestly spectacular.
- Next morning with coffee - yes, cold rhubarb crisp + a hot cup of coffee is a completely legitimate breakfast and we fully support it.
Can this rhubarb crisp be made ahead?
Yes! Assemble the full crisp up to 24 hours in advance, cover, and refrigerate. Add 10-15 extra minutes to the bake time when baking straight from the cold. You can also freeze just the oat topping for up to 3 months and sprinkle it frozen over a fresh filling on baking day.
Life gets busy, and this crisp has your back. A little planning ahead makes this a stress-free dessert for dinner parties, potlucks, or spring holiday gatherings.
- Assemble up to 24 hours ahead - put together the full crisp (filling + topping), cover tightly with plastic wrap, and refrigerate until ready to bake.
- Add 10-15 extra minutes to your bake time when going straight from the fridge to the oven to account for the cold dish.
- Freeze just the topping - the oat topping freezes beautifully for up to 3 months in a zip-top bag. When you're ready to bake, sprinkle it frozen directly over the fresh filling and bake as directed. No thawing needed.
Storing Leftovers
If you somehow end up with leftovers (absolutely no judgment if you don't), here's how to keep them tasting great:
- Room temperature: Cover loosely and store for up to 2 days. The topping will soften slightly after the first day - still delicious.
- Refrigerator: Store covered for up to 4 days. This is prime cold-crisp-and-coffee territory.
- Freezer: Freeze in an airtight container for up to 3 months. Thaw overnight in the refrigerator, then reheat in a 325°F oven until warmed through and the topping re-crisps - about 15-20 minutes.
Reheating tip
For the best texture, always reheat in the oven rather than the microwave. The microwave will warm it through, but the topping will go soft. A low oven brings back the crunch.
Frequently asked questions, answers and tips:
Nope, no pre-cooking needed! The rhubarb softens perfectly in the oven as it bakes. If your stalks are very thick or particularly underripe, you can simmer them in a small saucepan with a splash of water for about 5 minutes first for a softer, jammier filling. But for most fresh or frozen rhubarb, skip that step and go straight into the dish.
Great question. They're similar but not identical! A crisp includes oats in the topping, which is what gives it that signature crunchy, golden texture. A crumble is typically made with just butter, flour, and sugar no oats. Since this recipe uses old-fashioned rolled oats in the topping, it's officially a crisp.
Two likely culprits: the crisp was pulled from the oven before the filling was bubbling in the center, or there wasn't enough cornstarch to thicken the filling. Make sure you see active bubbling in the middle of the dish - not just around the edges - before taking it out. That bubble means the cornstarch has fully activated and your filling has set.
Almost always caused by one of three things: butter that was too warm when you made the topping, pressing the topping down onto the filling, or under-baking. Use cold butter straight from the fridge, keep the topping loose, and bake until deep golden brown.
Yes! For the best results, reheat individual portions in a 325°F oven for 10-15 minutes to restore that crispy topping. The microwave works in a pinch - heat in 20-30 second increments - but expect a softer topping.
More Rhubarb Recipes:
- Strawberry Rhubarb Jam - This strawberry rhubarb jam recipe can be made with fresh or frozen rhubarb and your choice of fresh or frozen strawberries.
- Strawberry Rhubarb Cast Iron Crisp - My mouth-watering strawberry rhubarb crisp recipe is easily made with minimum clean-up in a cast-iron skillet.
- Rhubarb Chutney - The perfect addition to any charcuterie board this easy chutney recipe is a delicious balance of savory, sweet and spice.
- Rhubarb Crumble - Rhubarb crumble is the one dish dessert that is delightfully tart, sweet with a crunchy topping that is delicious served warm with ice cream or chilled with a hot cup of coffee.
- Rhubarb Basil Smash - Tart rhubarb is balanced out with the sweet syrup and the muddling of basil gives the cocktail a brightness of flavor.
- Blackberry Dump Cake - Crunchy, sweet cobbler-like topping over blackberries is a delicious dessert.
- Rhubarb Jam - Rhubarb jam is so simple to make and a great jam recipe for beginners. The perfect balance of tart and sweet, this is the easiest homemade jam.
- Rhubarb Syrup
- Rhubarb Basil Smash Cocktail
Ingredients
Rubarb Crumble Filing
- 4 Cups (488 g) Rhubarb Fresh or frozen, Chopped in 1 inch pieces
- ½ Cup (100 g) Sugar
- 1 Tablespoon (1 Tablespoon) Lemon Juice
- 2 Tablespoons (2 Tablespoons) Cornstarch
- 1 Teaspoon (1 Teaspoon) Vanilla Extract
- ½ Teaspoon (½ Teaspoon) Cinnamon ground
- ½ Teaspoon (½ Teaspoon) Salt
- ¼ Teaspoon (¼ Teaspoon) nutmeg ground
Crumble Topping
- ⅓ Cup (41 ⅔ g) Flour, All Purpose
- ⅓ Cup (73 ⅓ g) Brown Sugar Light
- ⅔ Cup (54 g) rolled oats
- 6 Tablespoons (6 Tablespoons) Butter chilled, cubed
- ¼ Teaspoon (¼ Teaspoon) salt
Instructions
- Preheat oven to 375.
How to make rhubarb crumble
- Wash and chop the rhubarb into ½"-1" pieces. Do not include the leaves.4 Cups (488 g) Rhubarb
- Place the rhubarb in a baking dish and toss with the flour, cornstarch, lemon juice, vanilla extract, cinamon, salt and nutmeg until coated.4 Cups (488 g) Rhubarb, ½ Cup (100 g) Sugar, 1 Tablespoon Lemon Juice, 2 Tablespoons Cornstarch, 1 Teaspoon Vanilla Extract, ½ Teaspoon (½ Teaspoon) Cinnamon, ½ Teaspoon (½ Teaspoon) Salt, ¼ Teaspoon (¼ Teaspoon) nutmeg
- Allow the rhubarb to rest in the dish while you make the crumble topping.
Make the crumble topping
- Blend togetherthe crumble topping until the butter is crumbled together with the other crumble ingredients. The topping will resemble peas much like when you are making crisco pie crust.⅓ Cup (41 ⅔ g) Flour, All Purpose, ⅓ Cup (73 ⅓ g) Brown Sugar, ⅔ Cup (54 g) rolled oats, 6 Tablespoons Butter, ¼ Teaspoon (¼ Teaspoon) salt
- Crumble the topping over the rubbarb.
- Bake the rhubarb crumble for 45-55 minutes until the crumble topping is golden brown.
Nutrition
Notes
I am Sarah Mock. Welcome!
Sarah Mock is a classically trained Chef and a graduate of Johnson & Wales University. A culinary blogger for 17 years, Sarah helps the home cook prepare her recipes with professional results.
Comments
No Comments