Gluten-Free Strawberry Rhubarb Bars
These Gluten-Free Strawberry Rhubarb Bars make the best of summer’s rhubarb! This classic combination is a favorite for a reason – sweet, fragrant strawberries balance tart, buttery rhubarb to make a gorgeously pink filling.
Strawberry Rhubarb Bars Recipe
I am such a rhubarb fan, and I love it even more when it’s paired with strawberry and sandwiched by a gluten-free, lightly sweetened oat crust. These strawberry-rhubarb bars are a bit like your favorite fruity granola bar but a tad more of a dessert, especially topped with a scoop of vanilla ice cream. They’ll also make a perfect morning snack.
These bars aren’t fancy but they sure are satisfying. I’ve included a range of measurement for how much sweetener to use. I did four tablespoons of honey in the filling but if you find rhubarb too tart for your taste you could up it a bit. The sweetness of the strawberries so you could get away with less added sweetener if you choose.
This recipe is so simple it’ll come together in less than 10 minutes of active time so you can have a little treat to stash away for the coming weekend ahead — or, you know, tonight. My preference is to eat a bar straight from the fridge, when the fruit is cold and refreshing. However, bars are just lovely eaten outside on a late spring morning, preferably of course with a cup of coffee.
Love rhubarb as much as I do? Check out my other gluten-free rhubarb recipes including rhubarb upside cake, rhubarb cream cake, and strawberry-rhubarb jam.
Why You’ll Love These Gluten-Free Bars
There’s so much to love about these strawberry rhubarb bars! Here’s why I make them frequently while rhubarb’s in season:
- Naturally gluten-free. Oat flour and rolled oats form the base of the crust, and they are both whole grain and naturally gluten-free. The rest of the ingredients list is simple – fruit, a little sweetener, and some spices.
- So flavorful. Rhubarb – what else can I say about rhubarb? It is so unique, and has such a wonderful, almost buttery scent to it when it’s cooked. When rhubarb and strawberries are combined they create and amazing blend of sweet-tart that isn’t replicated by any other vegetable-fruit pairing.
- Not too sweet. As mentioned, you can adapt this recipe to be as sweet or not as you like. I love a recipe that starts off not being too sweet, so I can adjust it as necessary.
Ingredients Needed
Here’s what you’ll need to make these strawberry rhubarb bars. Check the recipe card at the end of this post for the full ingredient amounts.
For the Crust
- Oat Flour: Choose certified gluten-free oat flour if you’re sensitive.
- Old-Fashioned Rolled Oats: This are not the instant oats – they are the larger, coarse oats that are so great for baking.
- Brown Sugar: For a little sweetness.
- Ground Ginger: To add a bit of warming spice
- Baking Soda: To help bind the crust.
- Salt: I like fine sea salt in this recipe.
- Butter: I use unsalted butter. You could also use coconut oil,
For the Filling
- Rhubarb: Fresh rhubarb in season is essential!
- Strawberries: Ripe strawberries are the best but you can use frozen strawberries in a pinch.
- Honey: Sub maple syrup if you like.
- Arrowroot Powder: To thicken the filling. You could also use cornstarch.
- Vanilla Extract: For a hint of vanilla flavor.
How to Make Strawberry Rhubarb Bars
Make Crust
- Heat the oven and prepare the pan. Preheat oven to 350° F. Grease an 8×8-inch baking dish with coconut oil and line with parchment paper.
- Make the crust. In a large bowl, whisk together the oat flour, oats, coconut sugar, ginger, baking soda and salt. Stir in the melted butter and stir until dough begins to stick together.
- Place half of the filling in the pan. Place about 2/3 of the mixture in the baking dish and press flat using a rubber spatula and/or your hands. Put the remaining crust in the fridge until ready to use.
Make Filling
- Make the filling. In a large heavy saucepan, place the rhubarb, strawberries, honey, arrowroot, vanilla, and salt and stir to combine. Cook the fruit over medium heat until rhubarb has broken down and the mixture is bubbling and thick. Remove from heat and let cool slightly.
- Pour the filling onto the crust. When mixture has cooled a bit, pour it onto the prepared crust and spread out evenly. Remove the remaining crust from the fridge and sprinkle it evenly over the top of the fruit.
- Bake the bars. Place the pan in the oven and bake for 30-35 minutes or until filling is bubbly and topping is golden.
- Cool the bars. Remove from oven, place on a wire rack, and allow to cool full, then place in the fridge. Bars can be served room temperature or cold.
Substitution Suggestions
It’s super easy to make ingredient substitutions! Here’s how:
- Oat Flour – Sub sorghum flour.
- Make it Dairy-Free – Swap coconut oil for the butter.
- Make it Vegan – Swap coconut oil for the butter and maple syrup for the honey.
- Make it Refined Sugar-Free – Swap coconut sugar for the brown sugar.
Serving Suggestions
Here are a few ways to serve strawberry rhubarb bars:
- Warm and topped with ice cream. Vanilla or strawberry ice cream on top of warm slices of strawberry rhubarb crumble is my dream dessert.
- With whipped cream. You could also make lightly sweetened or unsweetened whipped cream to go with these gluten-free bars.
- Topped with fresh strawberries. Why not slice up some strawberries and serve them atop squares of rhubarb crumble?
Storage Options
Store leftover strawberry rhubarb bars, tightly covered in the pan or in an airtight container, in the fridge for up to 5 days. Serve warm, room temperature, or straight from the fridge.
Gluten-Free Strawberry-Rhubarb Bars
Ingredients
For Crust
- 1 ½ cups/160 g gluten-free oat flour
- 1 cup old-fashioned rolled oats
- ¼-½ cup brown sugar
- ½ teaspoon ground ginger
- ¼ teaspoon baking soda
- ¼ teaspoon fine sea salt
- ½ cup unsalted, melted butter
For Flling
- 1 stalks rhubarb, cut into ½-inch pieces
- 1 ½ cups strawberries, hulled and roughly chopped
- 3-5 tablespoons honey amount depending on preference
- 1 tablespoon arrowroot powder
- ½ pure vanilla extract
- ¼ teaspoon fine sea salt
Instructions
Make Crust
- Preheat oven to 350°F. Grease an 8×8-inch baking dish with butter and line with parchment paper.
- In a large bowl, whisk together the oat flour, oats, brown sugar, ginger, baking soda and salt. Stir in the melted butter and stir until dough begins to stick together.
- Place about ⅔ of the mixture in the baking dish and press flat using a rubber spatula and/or your hands. Put the remaining crust in the fridge until ready to use.
Make Filling
- In a large heavy bottom saucepan, place the rhubarb, strawberries, honey, arrowroot, vanilla, and salt and stir to combine. Cook fruit over medium heat until rhubarb has broken down and the mixture is bubbling and more thick. Remove from heat and let cool slightly.
- When mixture has cooled a bit, pour it onto the prepared crust and spread out evenly. Remove the remaining crust from the fridge and sprinkle it evenly over the top of the fruit.
- Place in the oven and bake for 30-35 minutes or until filling is bubbly and topping is golden.
- Remove from oven, place on a wire rack, and allow to cool full, then place in the fridge. Bars can be served room temperature or cold; keep covered in the fridge for 5 days.