Rhubarb Crisp Recipe (Old-Fashioned, Easy, and Perfectly Sweet-Tart)
This Rhubarb Crisp Recipe is everything I love about a cozy baked rhubarb dessert: a bubbling, sweet-tart fruit layer under a buttery, crispy oat crumble that makes the whole house smell like spring and comfort at the same time.
If you’ve got a bundle of fresh rhubarb on your counter and you’re not quite sure what to do with it, this simple rhubarb dessert is your new best friend. This classic rhubarb crisp recipe is the one I pull out as soon as the first pink-green stalks show up at our local Minnesota farmers market. It’s a little old-fashioned, a little nostalgic, and honestly, a lot easier than people expect. We use oats for a rustic, crispy oat crumble, dial in the sugar so the rhubarb still tastes bright, and bake it until the edges are bubbling and the topping is golden and crunchy.
I make this fruit crisp dessert for Sunday dinners, church potlucks, and any weeknight when I want something warm, cozy, and not too fussy. It also happens to be a good “starter” rhubarb baking recipe if you’re new to cooking with rhubarb—no fancy tools, no special skills, and very forgiving.
Why You’ll Love This Rhubarb Crisp Recipe
- Simple pantry ingredients: Everything you need for this easy rhubarb crisp is probably already in your kitchen—oats, flour, sugar, butter, and a big pile of rhubarb.
- Perfect sweet-tart balance: The filling is just sweet enough to soften the rhubarb’s tang without turning it into a sugary mush.
- Crispy oat crumble topping: That buttery crumble topping bakes into a golden, crispy oat crust that stays crunchy even with juicy fruit underneath.
- Flexible and forgiving: Use fresh or frozen rhubarb, add berries if you like, or tweak the sugar and spice to your taste.
- Great make-ahead dessert: Assemble it earlier in the day, tuck it into the fridge, and bake right before dinner for a warm rhubarb crisp coming out of the oven at just the right time.
- Easy to make gluten-free or dairy-free: Swap a couple of ingredients and you’ve got a crowd-friendly dessert for guests with different needs.
- Comfort food with a hint of wholesomeness: Rhubarb plus oats gives this classic rhubarb crisp a little fiber and structure—still dessert, just not over-the-top heavy.
- Works for casual or special occasions: It’s simple enough for a Tuesday night but also feels like a family favorite dessert for Mother’s Day or Easter brunch.
Ingredients
Let’s break this simple rhubarb crisp into two parts: the fruity base and that irresistible, buttery crumble topping. This makes one 9×13-inch pan of warm rhubarb crisp—plenty for a family, or for two people who love leftovers.
Rhubarb Filling
- 6 cups chopped rhubarb (about 1 ½ pounds, fresh or frozen; ½–¾-inch pieces)
- 1 cup granulated sugar (you can reduce to ¾ cup for a more tart dessert)
- 3 tablespoons cornstarch (helps thicken the juices so the crisp isn’t soupy)
- ¼ teaspoon fine sea salt
- 1 teaspoon pure vanilla extract
- 1 tablespoon fresh lemon juice (brightens the sweet tart rhubarb dessert)
Ingredient tips for the filling:
- Rhubarb: Look for firm, crisp stalks with bright color. Pale green is fine; color doesn’t affect flavor much. No need to peel unless the stalks are very thick and stringy.
- Frozen rhubarb: Thaw fully and drain off excess liquid before measuring. This helps prevent a watery filling.
- Sugar & cornstarch: If your rhubarb is very juicy or you’re mixing in other fruit like strawberries, keep the full 3 tablespoons cornstarch.
Crispy Oat Crumble Topping
- 1 ½ cups old-fashioned rolled oats (not quick oats)
- 1 cup all-purpose flour
- ¾ cup packed light brown sugar
- ½ cup granulated sugar
- 1 teaspoon ground cinnamon
- ¼ teaspoon ground nutmeg (optional but lovely)
- ½ teaspoon fine sea salt
- 1 cup (2 sticks) cold unsalted butter, cut into small cubes
Ingredient tips for the topping:
- Oats: Old-fashioned rolled oats give you that classic, rustic rhubarb oat topping with great texture.
- Butter: Use cold butter straight from the fridge for the crispiest, crumbliest topping. Soft or melted butter makes the topping more like a paste and less like a crumble.
- Spices: Cinnamon and a hint of nutmeg turn this from a plain fruit crisp into a deeply fragrant rhubarb comfort dessert.
Step-by-Step Directions for the Best Rhubarb Crisp
-
Preheat the oven and prep the pan.
Preheat your oven to 375°F (190°C). Lightly butter or spray a 9×13-inch baking dish. A glass or ceramic dish works best for even baking and pretty serving. -
Prep the rhubarb.
Wash the rhubarb stalks well and pat dry. Trim off the leaves (those are toxic—always discard), plus any dry ends. Slice the stalks into ½–¾-inch pieces so they cook evenly and soften without disappearing. -
Mix the rhubarb filling.
In a large bowl, combine the chopped rhubarb, 1 cup sugar, 3 tablespoons cornstarch, ¼ teaspoon salt, vanilla, and lemon juice. Toss until the rhubarb is evenly coated and you don’t see dry cornstarch. You’ll notice the mixture turning glossy as the sugar starts to draw out the juices. -
Spread the filling in the pan.
Pour the rhubarb mixture into your prepared baking dish and spread it out into an even layer. Make sure the cornstarch-sugar mixture doesn’t all sit in one spot—this helps your baked rhubarb dessert thicken evenly. -
Make the crispy oat crumble.
In another large bowl, stir together the oats, flour, brown sugar, granulated sugar, cinnamon, nutmeg (if using), and ½ teaspoon salt. Add the cold butter cubes. Using a pastry cutter, two forks, or your fingertips, cut the butter into the dry mixture until it forms pea-sized crumbs and clumps. You want some bigger clumps for texture—that’s what gives you that classic buttery crumble topping. -
Top the rhubarb filling.
Sprinkle the oat crumble evenly over the rhubarb filling. Don’t press it down too hard; light and fluffy helps it crisp up. Make sure you reach all the way to the corners so every bite gets a good amount of crispy oat crumble. -
Bake until bubbly and golden.
Bake on the center rack for 35–45 minutes, or until the rhubarb filling is bubbling up around the edges and through a few spots in the middle, and the topping is deep golden brown. If the topping browns too fast, loosely tent with foil for the last 10 minutes. -
Cool slightly before serving.
Let the old fashioned rhubarb crisp rest on a cooling rack for at least 15–20 minutes. This waiting time lets the juices thicken so the servings hold together a bit better—but it’s still wonderfully warm. -
Serve and enjoy.
Spoon warm rhubarb crisp into bowls and serve plain, with a scoop of vanilla ice cream, or a dollop of whipped cream. If you’re like my husband, you might even enjoy it cold for breakfast with a spoonful of Greek yogurt.
Servings & Timing
- Yield: About 8–10 servings
- Prep Time: 20 minutes
- Bake Time: 35–45 minutes
- Cooling Time: 15–20 minutes
- Total Time: About 1 hour 10 minutes
So, you’re looking at about 20 minutes of hands-on prep and the rest is just oven time and a short wait while the sweet-tart juices settle.
Fun Variations on This Simple Rhubarb Crisp
You know what? Once you have a solid base recipe like this, it becomes a blank canvas for all kinds of fruit crisp adventures.
- Strawberry Rhubarb Crisp: Swap 2 cups of rhubarb for 2 cups sliced strawberries for a very classic spring rhubarb recipe twist.
- Mixed Berry Rhubarb Crisp: Replace 2–3 cups of the rhubarb with blueberries, raspberries, or blackberries for a juicier fruit crisp dessert.
- Gluten-Free Rhubarb Crisp: Use a cup-for-cup gluten-free flour blend and make sure your oats are certified gluten-free.
- Nutty Crumble Topping: Add ½–¾ cup chopped pecans, walnuts, or sliced almonds to the oat topping for extra crunch and flavor.
- Lighter Sugar Version: Reduce the sugar in the filling to ¾ cup and in the topping to ½ cup brown sugar + ¼ cup granulated for a more tart, less sweet rhubarb dessert recipe.
- Individual Ramekins: Bake the oven baked crisp in small ramekins or mini skillets for cute single servings (check for doneness around 25–30 minutes).
Storage & Reheating
One of my favorite things about this family favorite dessert is how well it keeps. It actually tastes even better the next day.
- Room temperature: If your kitchen isn’t too warm, you can keep the baked crisp at room temperature, loosely covered, for up to 24 hours.
- Refrigerator: For longer storage, cover the pan tightly and refrigerate for 3–4 days. The topping will soften a little but still tastes wonderful.
- Freezer: Cool the crisp completely, then wrap the entire dish tightly with plastic wrap and foil, or transfer to airtight containers. Freeze for up to 2–3 months.
Reheating tips:
- For the best texture, reheat leftovers in a 350°F oven for about 15–20 minutes, or until warmed through and the topping has crisped back up.
- Individual servings can be reheated in the microwave for 30–45 seconds. The topping will be softer but still delicious.
- If reheating from frozen, thaw overnight in the fridge, then warm in a 350°F oven until hot and bubbly.
Make-ahead idea:
Assemble the rhubarb filling and oat topping in the pan, cover, and refrigerate for up to 24 hours before baking. When you’re ready, bake straight from the fridge, adding 5–10 minutes to the bake time.
Notes From My Kitchen to Yours
I’ve been making some version of this classic rhubarb crisp for over 25 years, and every spring I tweak it just a little—less sugar one year, more oats the next, sometimes a handful of berries from the freezer. Here are a few things I’ve learned along the way:
-
Adjust sugar to your rhubarb and your taste.
Younger, tender rhubarb tends to be less sour. Older, thicker stalks can be quite sharp. If you like a bold, tangy rhubarb comfort dessert, use the lower end of the sugar range. -
Don’t overwork the topping.
When you mix in the butter, stop when you see pea-sized crumbs and clumps. If it looks like cookie dough, you’ve gone too far and the topping may bake up dense instead of crumbly. -
Bake until you see active bubbling.
This matters more than the clock. Bubbling means the juices have thickened with the cornstarch and you won’t end up with a watery filling. -
Let it rest. I mean it.
I know it’s tempting to scoop into the crisp right out of the oven, but giving it at least 15 minutes helps the texture so much. Think of it like letting a roast rest—same idea, less dramatic. -
Use what you have.
No nutmeg? Skip it. Only light brown sugar? That’s fine. Real life baking is more about comfort and flavor than perfection.
If you enjoy this rhubarb baking recipe, you might also like a strawberry rhubarb crumble bar or even a simple apple crisp in the fall—once you’re comfortable with the basic fruit + crisp formula, you can play all year long.
FAQs About Rhubarb Crisp
Can I use frozen rhubarb in this rhubarb crisp recipe?
Yes, you can use frozen rhubarb. Thaw it fully, drain off extra liquid, and then measure it. This helps keep the filling from getting too watery.
Do I need to peel rhubarb first?
Usually no. Most rhubarb doesn’t need peeling. If a stalk is very thick and stringy, you can peel off the toughest outer strings with a small knife, but it’s rarely necessary.
Why is my rhubarb crisp soggy on top?
If the topping is soggy, it often means the butter was too soft or the crisp didn’t bake long enough. Next time, use cold butter and bake until the topping is deep golden and the filling is bubbling.
Can I make this rhubarb crisp dairy-free?
Yes. Use a dairy-free butter stick (the kind shaped like regular butter) in place of the regular butter. The texture will still be very close to the original.
Can I reduce the sugar in this recipe?
You can definitely cut the sugar in the filling to ¾ cup and in the topping by a couple of tablespoons. Just remember: less sugar means a more tart flavor, which some people love and others find a bit sharp.
What’s the best way to serve rhubarb crisp?
Warm, in a bowl, with something creamy on top—vanilla ice cream, whipped cream, or even a scoop of vanilla Greek yogurt. That combination of warm, tart rhubarb and cool cream is heaven.
How do I know when rhubarb is safe to eat?
Only the stalks are edible. The leaves are toxic and should always be discarded. As long as you remove the leaves and use fresh, crisp stalks, you’re good to go.
Can I make this recipe in a smaller pan?
Yes. You can bake it in a 9×9-inch square pan for a thicker layer of filling and topping. Add 5–10 minutes to the bake time and check for bubbling in the center.
Conclusion: A Cozy, Classic Rhubarb Dessert You’ll Make Again and Again
This Rhubarb Crisp Recipe is one of those “pass it down” kind of recipes—simple enough for a beginner baker, nostalgic enough to feel like it came from Grandma’s kitchen, and flexible enough to fit whatever fruit and pantry ingredients you have on hand. It’s a sweet tart rhubarb dessert with a buttery crumble topping that satisfies every time.
If you try this homemade rhubarb crisp, I’d love to hear how it turned out for you—tell me in the comments if you made any fun twists, or if it reminded you of a family recipe from your own childhood. And if you’re in a rhubarb mood, scroll around and check out my other spring rhubarb recipes for even more cozy, oven baked crisp ideas.
Rhubarb Crisp (Old-Fashioned, Easy, and Perfectly Sweet-Tart)
Ingredients
- 6 cups rhubarb about 1 1/2 pounds, fresh or frozen, chopped into 1/2–3/4-inch pieces
- 1 cup granulated sugar for the filling; reduce to 3/4 cup for a more tart dessert
- 3 tablespoons cornstarch helps thicken the juices
- 1/4 teaspoon fine sea salt for the filling
- 1 teaspoon pure vanilla extract
- 1 tablespoon fresh lemon juice
- 1 1/2 cups old-fashioned rolled oats not quick oats
- 1 cup all-purpose flour
- 3/4 cup light brown sugar packed, for the topping
- 1/2 cup granulated sugar for the topping
- 1 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg optional, for the topping
- 1/2 teaspoon fine sea salt for the topping
- 1 cup unsalted butter 2 sticks, cold, cut into small cubes
Instructions
- Preheat your oven to 375°F (190°C). Lightly butter or spray a 9x13-inch baking dish. A glass or ceramic dish works best for even baking.
- Wash the rhubarb stalks well and pat dry. Trim off and discard the leaves and any dry ends. Slice the stalks into 1/2–3/4-inch pieces so they cook evenly.
- In a large bowl, combine the chopped rhubarb, 1 cup granulated sugar, 3 tablespoons cornstarch, 1/4 teaspoon fine sea salt, vanilla, and lemon juice. Toss until the rhubarb is evenly coated and no dry cornstarch remains.6 cups rhubarb, 1 cup granulated sugar, 3 tablespoons cornstarch, 1/4 teaspoon fine sea salt, 1 teaspoon pure vanilla extract, 1 tablespoon fresh lemon juice
- Pour the rhubarb mixture into the prepared baking dish and spread into an even layer, making sure the cornstarch-sugar mixture is evenly distributed.
- In another large bowl, stir together the oats, flour, brown sugar, 1/2 cup granulated sugar, cinnamon, nutmeg (if using), and 1/2 teaspoon fine sea salt. Add the cold butter cubes and cut them into the dry ingredients with a pastry cutter, two forks, or your fingertips until you have pea-sized crumbs and clumps.1 1/2 cups old-fashioned rolled oats, 1 cup all-purpose flour, 3/4 cup light brown sugar, 1/2 cup granulated sugar, 1 teaspoon ground cinnamon, 1/4 teaspoon ground nutmeg, 1/2 teaspoon fine sea salt, 1 cup unsalted butter
- Sprinkle the oat crumble evenly over the rhubarb filling. Do not press it down; keep it light and fluffy so it crisps well. Cover the surface and reach into the corners so every bite has topping.
- Bake on the center rack for 35–45 minutes, or until the rhubarb filling is bubbling around the edges and in a few spots in the center, and the topping is deep golden brown. If the topping browns too quickly, loosely tent with foil during the last 10 minutes.
- Transfer the pan to a cooling rack and let the rhubarb crisp rest for 15–20 minutes. This allows the juices to thicken so the servings hold together better.
- Spoon the warm rhubarb crisp into bowls and serve plain or topped with vanilla ice cream, whipped cream, or a spoonful of Greek yogurt.
