This quick and easy gluten-free strawberry rhubarb crumble is generously topped with a simple oat-based streusel and is the perfect spring dessert!
I’m super excited to be posting this crumble today as it’s one of the first recipes I’m sharing from my new cookbook, The Sweet Side of Ancient Grains! It’s coming out next week and is all about 100% whole grain sweet treats. All of the recipes are created so that you can’t tell that they’re whole grain, which is especially helpful when you have stubborn kids or spouses who, like me, don’t like the taste of whole grains!
Several different ancient grains like buckwheat, quinoa and spelt are used throughout the book and all but a handful of the recipes include the option to use more common whole grains like white whole wheat flour or oats should you not like or have access to the ancient grains used. There’s also a good deal of gluten-free recipes in there, like this gluten-free strawberry rhubarb crumble.
I always try to make recipes dietary-friendly when possible so I tested this crumble with coconut oil for a dairy-free and vegan version and it’s just as delicious! Today’s recipe was adapted from a plum crumble in the book but with it being spring, I felt like a strawberry rhubarb version was in order.
If you can’t tell by the pictures, this crumble is pretty topping heavy – just the way I like it! You can easily use 50% more fruit if you want it a bit more balanced. And if rhubarb isn’t your favorite or if it’s not in season, just use more strawberries or another fruit. Just note that the baking time will likely be different. The plum version of this crumble only takes 25 minutes, while the strawberry rhubarb version took 40.
I was assuming that the tartness of the rhubarb would require that I add a little more sugar than most crumble recipes, so I took a gander at some other strawberry rhubarb crisp and crumble recipes. Most of them used double or even more sugar for the same amount of fruit that I used here. My strawberries hardly had any sweetness to them and I still found 1/4 cup to be enough. All that topping helps sweeten things quite a bit!
When baking anything with berries, I almost always add some lemon zest and extract but I thought I’d try something different with this crumble and added some almond extract. It adds a little something special, but lemon or more vanilla extract would also work!
Want to make something for a gluten-free friend but don’t want to invest in expensive gluten-free flours? This is the recipe for you! You just need some gluten-free oats and you’re good to go.
For more delicious gluten-free recipes, be sure to check out these Gluten-Free Samoa Cupcakes and these Gluten-Free Lava Cakes!

Gluten-Free Strawberry Rhubarb Crumble
This quick and easy gluten-free strawberry rhubarb crumble is generously topped with a simple oat-based streusel and is the perfect spring dessert!
Ingredients
For the fruit:
- 2 cups rhubarb, cut into 3/4" pieces
- 2 cups strawberries, hulled and cut into 3/4" pieces
- 1/4 cup granulated sugar
- 3/4 teaspoon almond extract
- 1/2 teaspoon vanilla extract
- 1 tablespoon cornstarch
- pinch of salt
For the topping:
- 3/4 cup + 1 tablespoon (75 grams) certified gluten-free oat flour*
- 1 1/4 cups (115 grams) certified gluten-free rolled oats
- 2/3 cup (132 grams) light brown sugar
- 2/3 cup (149 grams) butter or 1/2 cup + 1 tablespoon (126 grams) coconut oil**, melted and cooled slightly
- 1/4 teaspoon salt
Instructions
- Preheat the oven to 350°F and grease a 1-quart, 8"x8" or another similar sized baking dish.
- In a large mixing bowl, stir together the sugar, almond extract, vanilla extract, cornstarch and salt.
- Add the chopped fruit and stir to coat in the mixture. Let sit for at least 10 minutes while preparing the topping.
- In another large mixing bowl, stir together the oat flour, oats, brown sugar, melted butter or coconut oil and salt until well combined.
- Spoon the fruit mixture into the pan and top with the topping. Place the dish on a baking sheet to catch any spills.
- Bake for 40-45 minutes or until the topping is firm and the fruit is bubbling. The topping will appear to be quite runny around 25-30 minutes but firms up in the last 10-15 minutes of baking. The filling may also appear runny while warm but thickens as it cools.
- Let cool for 30 minutes and serve warm or room temperature. Cover and store at room temperature for up to 2 days.
Notes
- * To make oat flour, grind rolled or quick oats in a coffee grinder or small food processor until it resembles flour.
- ** For a dairy-free or vegan version, use coconut oil.
- If you need this to be gluten-free, make sure all your products are certified gluten-free.
Nutrition Information
Yield 12 Serving Size 1Amount Per Serving Calories 271Total Fat 20gSaturated Fat 16gTrans Fat 0gUnsaturated Fat 2gCholesterol 3mgSodium 67mgCarbohydrates 23gFiber 2gSugar 16gProtein 1g
Disclosure: Links within this post are affiliate links.
Shannon P
Monday 17th of July 2023
I made this yesterday but added blueberries and peaches. I only used one cup of rhubarb and cut the pieces smaller ( I also drizzle RD the fruit with a little lemon juice before adding the topping) . I used Almond flour instead of oat and this recipe turned out fabulous. Will definitely make this again when we have anyone visiting who is gluten free.
Jamie
Tuesday 18th of July 2023
Glad you enjoyed! Thanks for stopping by and sharing your feedback. Happy baking! Jamie
Ginger
Saturday 28th of May 2022
Great recipe! My husband really enjoyed it! Very easy to put together. :)
Jamie
Tuesday 31st of May 2022
So glad your husband enjoyed the crumble! Thanks for stopping by and sharing your feedback. Happy baking! -Jamie
Kristy
Sunday 21st of June 2020
I discovered my body doesn't like corn or corn starch. Do you recommend a specific replacement or will any starch work? I'm trying with arrowroot starch and fingers crossed.
Stephanie Ragucci
Wednesday 5th of July 2023
@Kristy, I used tapioca flour as a replacement for the cornstarch. It turned out amazing. You might want to look up the ratio, because you need more tapioca flour. I think I used 6 tablespoons instead of 4. Arrowroot should work out fine too.
Jamie
Saturday 27th of June 2020
Hello! I haven't attempted this recipe with a substitution for the cornstarch, so I am not sure of the result. If you happen to give it a try, I'd love to know how it turned out. Thanks so much for stopping by. -Jamie
fiona goble
Friday 24th of April 2020
Absolutely delicious and delightfully fuss free
Jamie
Sunday 3rd of May 2020
So happy to hear you enjoyed the crumble, Fiona! Thanks so much for stopping by and leaving your feedback! -Jamie
JS
Wednesday 17th of July 2019
This is the best simple gluten free crumble I have ever made. I added a bit of ground pecans and halved the sugar.
Jamie
Monday 22nd of July 2019
So happy to hear you enjoyed the crumble! Thanks so much for stopping by and leaving your feedback! -Jamie