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Full of tender apples and citrusy rhubarb, and crowned with a classic brown sugar oat crisp topping, Apple Rhubarb Crisp blends summer and fall together in sweet tart harmony. Move over strawberries! I can’t get enough of this one.
When you think of rhubarb, I bet you think of strawberries, right? Me, too. It’s a classic pairing for sure, but don’t let that stand in your way. We love rhubarb by itself (like with this simple rhubarb crisp) and I look forward to making this strawberry rhubarb crisp as well every summer. But rhubarb also pairs wonderfully with lots of other fruits. Here, it meets it’s match with apples.
Apple Rhubarb Crisp
This apple rhubarb crisp recipe creates a dessert that’s light enough to enjoy on hot days and warm enough for cool ones. So, it should come as no surprise that whenever there’s fresh rhubarb available, I stock up so that I can make this treat as often as I can. I’ve been baking crisps and cobblers for years now, and they’re still some of my favorite options for a no fuss, no muss dessert.
You’ll find that the balance of sweet and tart is great, here. The apples and rhubarb break down just enough into a tender, sweet baked treat that showcases the sweetness of the one with the tang of the other. Add in our favorite crunchy topping, and it’s no wonder that my boys and I love this crisp.
Ingredients and Substitutions
Filling Ingredients
Apples & Rhubarb – Tart apples and rhubarb make up the tender, juicy structure for the filling.
Sugar – I use regular white sugar to sweeten the filling for this crisp.
Cornstarch – I use a sprinkling of cornstarch to thicken the natural juices that are released by the apples, to help create the sauce.
Lemon Juice – You’ll want to use freshly squeezed lemon juice to brighten up the fruit flavors.
Cinnamon – The ground cinnamon brings warmth that pairs beautifully with the apples and with the rhubarb.
Salt – Yes, we use salt in sweet desserts! It is a flavor enhancer and I use kosher salt in all of my recipes unless specified otherwise.
Crisp Topping Ingredients
Oats – You’ll need old-fashioned oats here. It gives the topping a crispy, chewy bite.
Flour – Flour helps to bind the oats into a cohesive structure along with the butter. You can swap for a 1:1 gluten-free flour without issue, if that is a concern.
Brown Sugar – I sweeten the topping with light brown sugar.
Cinnamon – As with the filling, you’ll want to use cinnamon to add a warm sweetness and depth.
Butter – I use salted butter unless I tell you otherwise. The butter in the topping helps to bind the other ingredients together.
Notes on Equipment
- Measuring cups and spoons
- Mixing Bowls. I have a borderline absurd number of mixing bowls. It’s a thing. But I love knowing I have the right sizes to toss the apples and rhubarb in one bowl and stir up the oat topping in another. I’ve been using these daily for the last 8 years, and they’re still going strong.
- Cutting board
- Chef’s Knife. Chopping the apples and rhubarb into even half-inch pieces is so much easier with a quality knife, and even pieces cook at the same rate. I first tried Victorinox knives over 10 years ago while visiting a professional test kitchen. You could say it was love at first slice. The price point simply can’t be beat for the quality.
- A 2½-quart baking dish (about 9 or 10 inches)
How to Make Apple Rhubarb Crisp
Preheating the Oven: To start, you’ll need to preheat the oven to 350°F.
Chopping the Produce: While the oven is warming, I wash and slice the apples and rhubarb into half-inch pieces. I do not peel the apples, but feel free to do so, if that’s your preference.
Greasing the Pan: At this point, I also grease a 9-10″ baking dish with butter and set it aside so it will be ready when I need it.
Combining the Filling Ingredients: I’ll add the sliced apples and rhubarb to a mixing bowl. Then sprinkle them with the lemon juice, sugar, cornstarch, cinnamon and salt. I’ll give them a good toss to make sure the fruit is well coated.
Melting the Butter: I melt the butter in the microwave. Be careful because the dish can be quite hot.
Mixing the Crust: In another medium-sized bowl, you’ll stir together the oats, flour, brown sugar, cinnamon and melted butter.
Layering the Crisp: Spread out the fruit mixture across the greased pan with a spatula. Then, sprinkle the oat mixture on top of the fruit.
Baking: I pop the pan into the oven let it bake for 26-30 minutes. You’ll know the crisp is done when the crust has browned and the fruit mixture is bubbling.
Serving: Trust me, you do not want to bite into this right away. Those apple slices will be screaming hot, so I let it rest for a full 10 minutes before serving. I like to top each serving with vanilla ice cream or whipped cream.
Expert Tip
Because this recipe for apple rhubarb crisp balances a crunchy topping with a smooth, syrupy filling, it can be hard to check for doneness. As the baking time comes to a close, you’ll want to watch for browning, especially around the edge of the crust. The liquid fruit mixture should also be bubbling up slowly around the edges and in vents that form on top.
Slicing the Produce – Aim for uniform bite-sized pieces, about a half-inch thick. This ensures that they cook quickly, and finish at the same time. Otherwise, you end up with some that are raw in the middle while others are overdone mush.
Sprinkling the Crust – I like to use my hands to sprinkle the crust evenly across the top of the fruit mixture. This keeps you from having to spread it out with a spatula, and leaves naturally forming vents where the bubbles can escape.
Tent with Foil – This is something I don’t typically run into with my oven. But if yours runs hot, and you notice that the edges of the crisp are getting browner than you’d like while the center is not yet cooked, you can loosely wrap the edges with aluminum foil to keep the edges from burning.
Serving Suggestions
This kind of dessert basically demands ice cream, doesn’t it? And, the good news is that you can whip up ice cream without a machine in a flash using my no churn ice cream recipe.
And, when I don’t want to go to the trouble of making ice cream, but still want something fancy to finish this with, I look no further than a spoonful (or two!) of rhubarb sauce. Dessert is served.
Make Ahead & Storage
Make Ahead: Yes! This crisp can be made the day before you need it and it will still be great.
How to Store: I store leftovers in an airtight container in the fridge for up to 3 days.
How to Reheat: You don’t have to reheat this one. It’s great cold or hot. But, if you want to reheat it, you can just pop it into the microwave on 30 second increments and pull it when warm.
More Rhubarb Desserts
- Rhubarb Sauce
- Old Fashioned Rhubarb Pie
- Rhubarb Bars
- Rhubarb Cake with Butter Sauce
- Rhubarb Cobbler
- Rhubarb Oatmeal Bars
Frequently Asked Questions
No. If you use a thin-skinned variety of apple, you do not need to peel them. The peels will soften as it bakes, and you won’t notice the difference. It’s worth the time you save, too!
The fruit should be tender, but not mushy. The juices will thicken with the cornstarch as it bakes, too. So, it ends up being almost like a pie filling consistency when finished.
Before baking, the oat mixture should be moist, but not paste-like or spreadable. You’re looking for a mixing bowl full of small crumbs, not a cohesive batter.
Apple Rhubarb Crisp
Ingredients
- 4 large apples chopped into ½-inch pieces, about 6 cups
- 3 large rhubarb stalks cut into ½-inch pieces, about 2 cups
- 1 tablespoon lemon juice
- ¾ cup sugar
- 3 tablespoons cornstarch
- ¼ teaspoon ground cinnamon
- ¼ teaspoon kosher salt
Crisp Topping Ingredients
- 1 cup old-fashioned oats
- 1 cup all-purpose flour
- ½ cup light brown sugar
- ½ teaspoon ground cinnamon
- ½ cup butter melted
Instructions
- Preheat the oven to 350°F. Grease a 9 or 10-inch baking dish (about 2½ quart size) with butter. Combine the apples, rhubarb, lemon juice, sugar, cornstarch, and salt in a medium bowl. Stir to coat, then set aside.
- In another bowl, stir together the oats, flour, brown sugar, cinnamon, and butter. Pour the fruit into the greased pan, then sprinkle the oat mixture on top of the fruit.
- Bake for 26-30 minutes, until the crust has browned and the fruit mixture is bubbling. Let cool for 10 minutes before serving warm, topped with vanilla ice cream or whipped cream.
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Your instructions in the actual recipe don’t mention apples. I assume I put them in with the rhubarb and lemon juice mix?
Thanks for catching that! Yes, you’ll add the apples with the rhubarb.