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These nut-free, gluten-free strawberry crumble bars deliver a jammy strawberry-rhubarb filling and a crisp golden topping in 45 minutes, thanks to arrowroot for thickness and 1:1 gluten-free flour for structure- sliceable, sweet-tart, and picnic-ready.
Recipe Breakthrough: Nut-Free Meets Gluten-Free
Reader requests for a rhubarb treat pushed me to find a crumble bar that everyone can enjoy. Swapping in King Arthur 1:1 Gluten-Free Flour kept the crust sturdy without any almonds or oats, so the bars stay crisp and allergy-friendly.
Craving more gluten-free crisps? Try my mixed berry crisp or cozy grain-free apple crisp next. If strawberries are your thing, don't miss this paleo strawberry shortcake or these cheesecake bars!
Ingredients You'll Need
- Strawberries + Rhubarb: Fresh or frozen work great. The arrowroot prevents a soupy filling.
- Lemon Juice: Brightens the fruit.
- Arrowroot Powder: Gluten-free thickener that sets juices fast.
- Butter: Cold and cubed. Swap coconut oil for dairy-free.
- Gluten-Free 1:1 Flour Blend: Already contains xanthan gum for lift.
- Sugar, Baking Powder, Salt, Egg, Vanilla: Pantry basics for sweetness and structure.
How to Make Gluten-Free Strawberry Rhubarb Crumble Bars
Step 1: Heat oven to 375°F. Line a 9×9-inch pan with parchment. In a bowl, toss strawberries, rhubarb, lemon juice, sugar, and arrowroot. Set aside.
Step 2: In a food processor, pulse flour, sugar, eggs, baking powder, and salt. Add butter and pulse to pea-size crumbs. You’ll have a clumpy dough.
Step 3: Press half the dough firmly into the pan for a compact crust.
Step 4: Spoon fruit evenly on top, pressing lightly so pieces lie flat.
Step 5: Crumble remaining dough over the fruit, leaving some gaps for steam. Bake 35-40 minutes until the topping is golden and the fruit bubbles. Cool completely, then cut into 16 squares.
Topping & Texture Fixes
- Pale topping? Broil the finished pan 60 seconds for added color.
- Too much juice? Increase arrowroot to 1 ½ tablespoons for frozen fruit.
- Burning crumbs? Tent loosely with foil at the 25-minute mark.
Expert Tips
- Dairy-Free: Replace butter with cold coconut oil, then chill the crumble for ten minutes before pulsing. The extra chill keeps the topping clumpy and crisps up just like butter- no dairy required.
- Make Ahead Tips: Bake, cool, and slice. Freeze bars on a sheet pan, then store stacked with parchment for up to three months. Thaw 30 minutes at room temp for bakery-style edges.
Recipe FAQs
Yes. Use 3 cups diced berries. Keep the arrowroot the same.
Botanically, it’s a vegetable, but U.S. law classifies it as a fruit for trade.
Over-mixing the dough creates excess starch. Make sure to pulse just until combined.
Store covered in the fridge up to five days.
More Fruit-Filled Desserts
Gluten Free Strawberry Rhubarb Crumble Bars
Equipment
Ingredients
Filling
- 1 ½ cups diced strawberries
- 1 ½ cups diced rhubarb, sliced into ¼ inch thick
- 1 tbsp fresh lemon juice
- ⅓ cup granulated sugar
- 1 tbsp arrowroot powder
Crust & Crumble Topping
- 2 cups King Arthur Gluten Free 1:1 Flour
- ⅔ cup granulated sugar
- 1 tsp baking powder
- ¼ tsp salt
- ¾ cup unsalted butter, cut into chunks
- 1 egg
- 1 tsp vanilla
Instructions
- Preheat oven to 375. Spray or line a 9×9 baking pan with parchment paper.
- Combine the filling ingredients in a bowl and stir to combine. Let them sit on the counter while you make the crust and crumble topping.
- Combine the crust/crumble ingredients in a food processor and pulse until a dough forms. Press half of the dough into the bottom of the pan to create an even crust.
- Add the strawberry rhubarb filling on top and spread out evenly using a spatula. Press down slightly so the strawberries are lying flat.
- Use your hands to place small pieces/crumbles of the remaining dough on top to form the topping until it's all used up.
- Bake at 375 for 35-40 minutes until the bars are slightly browned. Let them cool completely, then carefully cut into16 squares. Enjoy!
Notes
- Dairy-Free: Replace butter with cold coconut oil, then chill the crumble for ten minutes before pulsing. The extra chill keeps the topping clumpy and crisps up just like butter- no dairy required.
- Make Ahead Tips: Bake, cool, and slice. Freeze bars on a sheet pan, then store stacked with parchment for up to three months. Thaw 30 minutes at room temp for bakery-style edges.
Nutrition
All nutrition facts are an estimate and automatically calculated. While I fact check them using My Fitness Pal, please note that they may not always be 100% accurate and depend on ingredients used. Weigh your total and divide by the number of servings for the most accurate grams per serving size.
