Few desserts say “summer” like a warm raspberry rhubarb crisp fresh from the oven. With its tart-sweet filling and golden oat topping, it’s the kind of dish that brings people running. In this post, I’m sharing my go-to raspberry rhubarb crisp recipe—easy to make, rich in texture, and perfectly balanced. I’ve added metric conversions, expert tips, and a foolproof topping that stays crisp even after cooling. Whether you’re using frozen fruit or just raided the garden, this is the dessert you’ll make on repeat.
Table of Contents
Table of Contents
A Crisp That Started It All
The First Crisp That Hooked Me
Hey, I’m Ava. If you’ve seen my chaos-in-the-kitchen moments online, you know I’m not a formal chef—I’m a late-night experimenter with a thing for flavor bombs. The first raspberry rhubarb crisp I ever made was a total accident. I had a fridge full of rhubarb, some leftover berries, and no plan. I guessed my way through the sugar and flour, baked it too long, and still? It was ridiculously good.
That rough version was enough to start a tradition. I’ve since fine-tuned every element, from butter temperature to how long the filling needs to sit. This is the recipe I go back to—simple, quick, and flexible enough for any pantry or crowd.
Why This Version Always Delivers
This raspberry rhubarb crisp recipe leans on the classics with a few upgrades. The topping? Extra crisp, thanks to cold butter cut into oats and flour. The filling thickens as it bakes because we rest it with sugar and cornstarch first. You don’t need fancy tools or obscure ingredients—just a few good habits and a baking dish. I’ve also tested it with frozen fruit, and it still turns out great.
Raspberry Rhubarb Crisp
Equipment
Ingredients
Instructions
Notes
What You’ll Need & How to Make It
Ingredients (Cups + Grams)
For the Fruit Layer
- 3 cups (360g) rhubarb, chopped
- 2 cups (240g) raspberries
- ¾ cup (150g) white sugar
- 2 tbsp (16g) cornstarch
- 1 tsp vanilla extract
- Optional: zest from one lemon
For the Crumble Topping
- 1 cup (80g) rolled oats
- ¾ cup (95g) flour
- ⅔ cup (130g) brown sugar
- ½ tsp cinnamon
- ½ tsp salt
- ½ cup (115g) butter, cold and diced
This combo gives the raspberry rhubarb crisp a golden crust and juicy base with just the right chew.
Instructions
- Preheat your oven to 375°F (190°C) and lightly grease a square baking dish (around 9×9).
- Combine the filling. In a bowl, mix rhubarb, raspberries, sugar, cornstarch, vanilla, and lemon zest. Set aside for 10 minutes to allow the juices to start thickening.
- Make the topping. In a separate bowl, whisk together oats, flour, brown sugar, cinnamon, and salt. Add the cold butter cubes and work it into the dry ingredients until the mixture resembles rough crumbs.
- Layer it. Spoon the fruit mixture into the baking dish. Sprinkle the topping evenly over the surface.
- Bake. Place the dish on a baking sheet to catch any drips. Bake uncovered for 40–45 minutes until the surface is golden and the filling is bubbling at the edges.
- Cool slightly. Let your raspberry rhubarb crisp rest at room temperature for 15–20 minutes before serving.
Custom Options & Smart Baking Tips
Variations for Every Kitchen
This raspberry rhubarb crisp is easy to adjust depending on your dietary needs:
- Gluten-Free? Use GF-certified oats and your favorite 1:1 gluten-free flour mix.
- Vegan? Swap the butter for coconut oil or plant-based margarine—keep it cold!
- Nut-Free? This version is nut-free, but you can add chopped pecans if you want a bit more crunch.
The texture and flavor stay spot-on no matter which variation you use.
Pro Tips for Perfect Crisp Texture
- Cold butter is everything. It creates pockets of air that crisp up instead of melting into mush.
- Let the fruit sit. Giving the filling time to rest allows the cornstarch to activate and avoid a runny center.
- No foil or cover. Baking uncovered helps the topping brown evenly without trapping moisture.
Once you’ve mastered this raspberry rhubarb crisp, you’ll find yourself remixing it with whatever fruit you have on hand.
Common Questions & Fixes
Can I use frozen fruit?
Yes—frozen rhubarb and raspberries work great. Use them straight from the freezer. Just toss in an extra teaspoon of cornstarch to help manage the extra juice.
Why didn’t my topping crisp?
The butter might’ve softened too much or been overmixed. Keep it cold and avoid pressing the crumble down into the fruit. Also, be sure to leave the raspberry rhubarb crisp uncovered during baking.
What’s the best way to store it?
Let your crisp cool, then cover it with foil or store in a sealed container. Refrigerate for up to 4 days.
To refresh the texture, warm individual servings in an oven-safe dish at 350°F (175°C) for 10 minutes.
Can I prep it in advance?
You can assemble the full raspberry rhubarb crisp (uncooked), then refrigerate it for up to a day. If you want to freeze it, wrap it tightly and bake from frozen, adding about 10 minutes to the total cook time.
Final Troubleshooting Notes
- Runny filling? Increase cornstarch slightly and let the fruit rest longer before baking. Also, be sure it bubbles for at least 5 minutes in the oven.
- Dry topping? A bit too much flour or overbaking can cause this. Aim for crumbly, not dusty, when mixing your topping.
Craving more sweet magic? Try these next:
- Rhubarb Cookies Recipe with Oatmeal Glaze – A chewy twist on rhubarb, wrapped in warm oats and finished with a dreamy glaze
- Easy Strawberry Crumb Cake – Buttery, berry-packed, and crowned with a golden crumb
- The Best Chocolate Raspberry Cake – Deep chocolate meets tart raspberries in every decadent bite
Want to see how I use these Chewy Rhubarb Oatmeal Cookies (with Lemon Glaze) in real time?
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