Strawberry Rhubarb Crumble Bars are a sweet and tangy treat that perfectly blends fresh strawberries with the bright tartness of rhubarb. These bars have a crumbly, buttery crust and topping that adds a lovely texture, making every bite a little bit crunchy and a little bit soft with fruit filling in the center.
I love making these bars when both strawberries and rhubarb are in season because the flavors just pop. The balance between the sweet strawberries and the sharp rhubarb keeps these bars from being too sugary, which I really appreciate. Plus, the crumble topping is my favorite part – I always sneak a few crumbs before the bars even leave the kitchen!
These bars are wonderful served slightly warm or at room temperature, and they’re perfect for sharing at picnics, potlucks, or just as a simple dessert after dinner. I often like to add a little scoop of vanilla ice cream on top for an extra cozy touch. Whether you’re new to rhubarb or already a fan, these bars make a great way to enjoy the season’s fresh flavors all in one bite.
Key Ingredients & Substitutions
Butter: Using unsalted butter lets you control the salt level. Make sure it’s softened to blend properly with sugar and flour. If you need a dairy-free option, try vegan butter or coconut oil, but the flavor and crumble may change a bit.
Strawberries & Rhubarb: Fresh fruit makes a big difference. If rhubarb is hard to find, you could swap it with tart apples or cranberries for a similar tang. Frozen fruit works too but thaw and drain excess liquid to avoid soggy bars.
Cornstarch: This thickens the fruit filling so it’s not runny. If you don’t have cornstarch, try arrowroot powder or tapioca starch instead.
Oats (Optional): Adding oats to the crumble topping gives extra texture and nuttiness. Rolled oats work if you don’t have quick oats, but they’ll be chunkier.
How Do I Get the Perfect Crumble Texture?
The crumble topping should be a mix of larger and smaller crumbs to add crunch and tenderness. Here’s how I like to do it:
- Cut cold butter into the flour and sugar using a pastry cutter or your fingers. The mixture should look like coarse crumbs with some pea-sized pieces.
- Don’t overwork the dough—you want bits of butter visible before baking to create a flaky texture.
- Press the crust layer firmly and evenly in the pan, but leave the topping loose and crumbly.
- Bake until the topping is golden brown and the fruit filling bubbles up at the edges; this usually takes about 40-45 minutes.
Equipment You’ll Need
- 9×13-inch baking pan – It’s the perfect size for even baking and easy removal of the bars.
- Parchment paper – Keeps the bars from sticking and makes cleanup easier.
- Mixing bowls – For preparing the crust, fruit filling, and crumble topping.
- Whisk or fork – To mix dry ingredients evenly and cut in the butter for the crumble.
- Measuring cups and spoons – To measure ingredients accurately for consistent results.
Flavor Variations & Add-Ins
- Try blueberries or raspberries with the strawberries and rhubarb for extra berry flavor.
- Mix in chopped nuts, like almonds or pecans, into the crumble topping for crunch and richness.
- Add a pinch of cinnamon or ginger to the fruit mixture for warm, spicy notes.
- Swap vanilla with lemon or orange zest in the crust or fruit filling for a citrus twist.
Strawberry Rhubarb Crumble Bars
Ingredients You’ll Need:
For the Crust and Topping:
- 1 cup (2 sticks) unsalted butter, softened
- 1 cup granulated sugar, divided
- 1 teaspoon vanilla extract
- 2 1/2 cups all-purpose flour
- 1/2 teaspoon salt
- 1/3 cup quick oats (optional, for extra texture in crumble topping)
For the Fruit Filling:
- 1 1/2 cups fresh strawberries, chopped
- 1 1/2 cups fresh rhubarb, chopped
- 2 tablespoons cornstarch
- 1 tablespoon lemon juice
- 1/4 cup brown sugar (optional, for extra sweetness)
How Much Time Will You Need?
This recipe takes about 15 minutes to prepare and 40-45 minutes to bake. Then allow the bars to cool completely, about 1 hour, before cutting and serving. All together, plan for around 1 hour and 15 minutes from start to finish.
Step-by-Step Instructions:
1. Prepare the Oven and Pan:
Preheat your oven to 350°F (175°C). Line a 9×13-inch baking pan with parchment paper, leaving an overhang on the sides for easy removal later.
2. Make the Crust and Topping Base:
In a large bowl, cream together softened butter and 3/4 cup sugar until light and fluffy. Stir in vanilla extract. In a separate bowl, whisk together flour and salt, then gradually add it to the butter mixture. Mix until the dough is crumbly but sticks together when pressed.
3. Create the Crust:
Reserve about 1 1/2 cups of the crumb mixture for the topping. Press the remaining crumbs firmly and evenly into the bottom of your prepared pan to form the crust layer.
4. Prepare and Add the Fruit Filling:
In a bowl, combine chopped strawberries, rhubarb, remaining 1/4 cup sugar, brown sugar (if using), cornstarch, and lemon juice. Toss until fruit is well coated. Spread this mixture evenly over the crust.
5. Top and Bake:
If using oats, mix them into the reserved crumb mixture now for extra texture. Sprinkle the crumble topping evenly over the fruit layer. Bake for 40-45 minutes until the topping is golden and the fruit filling bubbles around the edges.
6. Cool and Serve:
Let the bars cool completely in the pan on a wire rack. Use the parchment paper edges to lift the bars out of the pan and place on a cutting board. Cut into squares. Enjoy them at room temperature or chilled.
Can I Use Frozen Strawberries and Rhubarb?
Yes! Just make sure to thaw and drain them well before using to avoid excess moisture, which can make the bars soggy.
How Should I Store Leftover Bars?
Store leftovers in an airtight container in the fridge for up to 4 days. You can enjoy them cold or warm them slightly in the microwave before serving.
Can I Make These Bars Gluten-Free?
Absolutely! Substitute the all-purpose flour with a gluten-free flour blend that measures cup-for-cup. Just make sure it includes xanthan gum or add a bit yourself for structure.
Is It Okay to Skip the Oats in the Topping?
Yes, the oats add extra texture but are completely optional. The crumble will still be delicious and buttery without them.