Strawberry Rhubarb Crumble Bars are the perfect mix of sweet and tangy, with juicy strawberries and tart rhubarb nestled beneath a buttery, crumbly topping. The bars have a delightful balance of textures — soft fruit filling paired with a crunchy, golden crust that holds everything together beautifully.
I love making these bars because they remind me of sunny afternoons and backyard picnics. They’re not too sweet, which means you get that fresh rhubarb zing with every bite, and the crumble on top adds a nice little crunch. Trust me, the smell drifting from the oven while these bake will have everyone peeking into the kitchen!
One of my favorite ways to enjoy these bars is warm, right out of the oven, maybe with a scoop of vanilla ice cream or a dollop of whipped cream. They’re a great treat to share with friends and family, whether it’s a casual coffee break or a special dessert after dinner. Plus, they’re easy to slice and carry, making them an ideal recipe for potlucks or packed lunches.
Key Ingredients & Substitutions
Strawberries and Rhubarb: Fresh is best for a juicy, tangy filling. If fresh rhubarb isn’t available, frozen works too—just thaw and drain first to avoid extra liquid. You can swap strawberries with raspberries or cherries for a twist.
Rolled Oats: These add a nice texture to the crumble and crust. If you don’t have oats, you can use more flour, but you’ll lose some crunch.
Butter: Unsalted butter is great for controlling saltiness and flavor. You can use salted butter and skip the extra salt if needed. For a dairy-free option, try coconut oil, but expect a slightly different texture.
Cornstarch: This thickens the fruit filling. If you don’t have cornstarch, arrowroot or tapioca starch work well too.
How Do I Get the Perfect Crumbly Crust and Topping?
Getting the crumbly texture on both the bottom and top layers is all about mixing and baking:
- Mix the dry ingredients well before adding melted butter. Use a fork or your fingers to combine until the mixture looks like coarse crumbs.
- Press two-thirds of this crumb mixture firmly into the pan for a solid base. This helps it hold together when cutting later.
- Sprinkle the remaining crumbs loosely over the fruit filling to keep the topping light and crunchy.
- Bake until the top is golden and the filling is bubbling; this means the fruit is cooked and the crust is crisp.
- Let the bars cool fully so the filling sets and doesn’t spill when sliced.
Following these tips will give your crumble bars a balanced crunch and hold together nicely when you serve them.
Equipment You’ll Need
- 9×13 inch baking pan – I like using this size because it’s perfect for even baking and easy to cut into bars.
- Parchment paper – helps lift the bars out cleanly and prevents sticking.
- Large mixing bowls – for combining the crumble ingredients and fruit filling without mess.
- Measuring cups and spoons – to get the right amount of each ingredient easily.
- Whisk or fork – for mixing the crumbs and blending ingredients smoothly.
- Spatula – to press the crumble mixture evenly into the pan and spread the fruit filling.
Flavor Variations & Add-Ins
- Swap strawberries and rhubarb for cherries or blueberries for a different fruity flavor profile.
- Add a splash of almond or lemon extract to the fruit filling for a bright, fresh taste.
- Mix in chopped nuts like walnuts or pecans into the crumble for extra crunch and flavor.
- Use gluten-free oats and flour if you want a gluten-free version of these bars.
How to Make Strawberry Rhubarb Crumble Bars?
Ingredients You’ll Need:
For the Crust and Crumble:
- 2 cups all-purpose flour
- 1 1/4 cups old-fashioned rolled oats
- 1 cup granulated sugar
- 1/2 teaspoon salt
- 1 teaspoon baking powder
- 1 cup unsalted butter, melted
For the Strawberry Rhubarb Filling:
- 2 cups fresh strawberries, hulled and chopped
- 2 cups rhubarb, chopped into 1/2-inch pieces
- 3/4 cup granulated sugar
- 2 tablespoons cornstarch
- 1 teaspoon vanilla extract
- 1/4 teaspoon ground cinnamon (optional)
How Much Time Will You Need?
You’ll spend about 15 minutes preparing the ingredients and assembling the bars. Bake time is around 45-50 minutes. Then, allow about 1 hour for cooling so the bars set well before slicing and serving.
Step-by-Step Instructions:
1. Preheat and Prepare the Pan:
Begin by heating your oven to 350°F (175°C). Line a 9×13-inch baking pan with parchment paper, leaving some overhang along the sides — this will help you lift the bars out easily when they’re baked.
2. Make the Crust and Crumble:
In a large bowl, mix the flour, rolled oats, sugar, salt, and baking powder together. Pour in the melted butter and stir until the mixture looks crumbly but holds together when pressed. This will form the crunchy base and topping.
3. Form the Base Layer:
Take about two-thirds of the crumble mixture and press it firmly and evenly into the bottom of your prepared pan. This is your crust, so press well to help it stick together while baking.
4. Prepare the Fruit Filling:
In a separate bowl, toss the chopped strawberries and rhubarb with sugar, cornstarch, vanilla extract, and cinnamon (if using). Mix until all the fruit is coated evenly. This mix will give you a delicious, slightly thickened filling.
5. Assemble the Bars:
Spread the fruit mixture evenly over the crust layer. Then, sprinkle the remaining crumble mixture evenly on top to create the crunchy topping.
6. Bake the Bars:
Bake in your preheated oven for 45-50 minutes. The crumble topping should turn a lovely golden brown, and you’ll see the fruit filling bubbling gently around the edges.
7. Cool and Serve:
Take the bars out of the oven and let them cool completely in the pan on a wire rack — about 1 hour. Once cooled, lift the bars out using the parchment paper and cut them into squares.
8. Enjoy!
Serve your Strawberry Rhubarb Crumble Bars as is, or add a scoop of vanilla ice cream or a dollop of whipped cream for an extra special treat. Enjoy the perfect mix of sweet, tart, and crunchy!
Can I Use Frozen Strawberries and Rhubarb?
Yes, you can use frozen strawberries and rhubarb. Just make sure to thaw them completely and drain any excess liquid before mixing with the sugar and cornstarch to prevent a soggy filling.
How Should I Store Leftover Bars?
Store leftover bars in an airtight container in the refrigerator for up to 4 days. You can enjoy them cold or warm them slightly in the microwave for a fresh-baked feel.
Can I Make These Bars Gluten-Free?
Absolutely! Use gluten-free all-purpose flour and certified gluten-free oats to make these crumble bars safe for gluten-sensitive diets.
What’s the Best Way to Cut the Bars Cleanly?
Wait until the bars are completely cool to cut them. Use a sharp, serrated knife and wipe it clean between cuts to get neat, clean edges without crumbling.