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Recipe

Rhubarb Crisp Recipe

Tart, jammy rhubarb under a buttery oat topping that bakes up crisp, craggy, and golden. Easy ingredients, big flavor, zero fuss.

Author By Matt Campbell
4.8
A golden rhubarb crisp in a white baking dish with bubbling ruby filling and a crisp oat topping on a rustic wooden table
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If rhubarb has ever made you nervous, I get it. It looks like celery’s sassier cousin and tastes like it has opinions. But baked into a crisp? Absolute magic. You get a bright, tangy filling that turns glossy and jammy in the oven, topped with a buttery oat crumble that lands somewhere between cookie and granola bar, in the best way.

This is my go-to rhubarb crisp: a filling that actually thickens (no pink soup), plus a topping that bakes up golden, clumpy, and confidently crunchy. It will soften a bit in the fridge because physics, but it re-crisps like a champ. Keep it classic with vanilla ice cream, or go rogue with Greek yogurt for breakfast. No judgment. Minimal drama. Maximum crunch.

A close-up of a spoon scooping rhubarb crisp showing jammy pink filling and crunchy oat crumble

Why It Works

  • Big contrast: tart rhubarb gets sweetened just enough, then baked until jammy under a deeply golden topping.
  • No sad topping: we use melted butter and a smart flour to oat ratio so it clumps and crisps instead of turning sandy.
  • Filling that sets: cornstarch thickens the juices as they bubble, so you can scoop clean portions after a short rest.
  • Accessible ingredients: nothing fancy required, but you still get that bakery-level crunch.

Pairs Well With

Storage Tips

Cool it down first. Let the crisp cool so it can set and so steam does not immediately soften the topping. For food safety, get it into the fridge within about 2 hours (sooner if your kitchen is very warm).

Fridge

  • Cover the baking dish tightly or transfer to an airtight container.
  • Store for 3 to 4 days (best within the first few days).

Freezer

  • Freeze in portions for up to 2 months for best quality (it can last a bit longer, but the texture is happiest in that window).
  • For best crunch, thaw overnight in the fridge before reheating.

Reheating for maximum crunch

  • Oven: 350°F for 12 to 18 minutes until hot and the topping re-crisps.
  • Air fryer: 320°F for 5 to 8 minutes for smaller portions.
  • Microwave: works in a pinch, but the topping will soften. If you microwave, finish with 3 to 5 minutes in a toaster oven if you can.

Common Questions

Do I need to peel rhubarb?

Usually, no. If the stalks are very thick or stringy, you can peel the tougher outer strings like you would celery. Most fresh rhubarb softens beautifully as is.

Can I use frozen rhubarb?

Yes. You can bake it straight from frozen. Do not thaw it first. Toss frozen rhubarb with the sugar, cornstarch, and seasonings, then bake. Frozen fruit can run extra juicy depending on the brand and cut, so plan on 5 to 10 extra minutes and, if needed, bump the cornstarch up to 2 1/2 to 3 tablespoons.

Why is my crisp watery?

Three common culprits: not enough thickener, not baking long enough for the filling to bubble, or not resting after baking. The cornstarch needs that bubbling heat to activate, and the rest time helps everything set.

How do I keep the topping crunchy?

Use melted butter to form clumps, bake until deeply golden, and reheat in the oven instead of the microwave. Crisps do soften in the fridge because humidity happens, but this one re-crisps really well.

Can I reduce the sugar?

A little, yes. Rhubarb is aggressively tart. If you cut too much sugar, you will taste it. Start by reducing the filling sugar by 2 tablespoons and see how you feel.

Is this the same as a crumble?

They are cousins. A crisp usually has oats in the topping. A crumble often skips the oats. Either way, you are getting a buttery topping over baked fruit, and I am on board.

Can I make it ahead?

Yes. For the best texture, mix the filling and put it in the baking dish, then make the topping and keep it in a separate container. Refrigerate both up to 24 hours, then top and bake. If your topping firms up in the fridge, just break it into clumps with your fingers before sprinkling.

My first real rhubarb moment happened because someone handed me a bag of stalks like it was a normal Tuesday errand. I chopped it up, tasted a raw piece, and immediately understood why sugar exists. The crisp was my fix. Rhubarb keeps its attitude, but in the oven it turns into this bright, jammy filling that tastes like spring decided to show off. The topping is where I get a little chaotic. I want clumps, crunch, and edges that practically snap. This recipe is the one I make when I want dessert that feels cozy but still wakes up your taste buds.