Strawberries, blackberries, and blueberries come together in a jammy, sweet filling nestled between a buttery shortbread crust and a crunchy crumble topping. These summery berry crumble bars are perfect for parties or any time you crave a fruity, cookie-style bar.

I adore summer fruit in desserts — from cherry and loquat cobblers to peach hand pies — but berries are my favorite. Every season I experiment with new ways to highlight that bright, sweet-tart flavor. After perfecting a mixed berry cobbler and a silky strawberry syrup, I created these irresistible berry crumble bars. They use a simple shortbread cookie crust as the base, and leftover shortbread is crumbled on top to form a tender, buttery topping that pairs beautifully with the fruit.
Recipe Highlights
- Big berry flavor – Three berries blend into a sweet, slightly tart, jam-like filling. Swap the fruit to suit your taste.
- Shareable – Cookie bars make a large, easy-to-serve dessert with no shaping or scooping required.
Ingredients & Substitutions
The recipe has two parts: the shortbread (used for the crust and crumble) and the berry filling. Below are the essential ingredients and simple substitution options.

- Shortbread crust + crumble: all-purpose flour, unsalted butter (or vegan butter), powdered sugar (or granulated), vanilla, lemon zest, and a pinch of salt.
- Berries: a mix of fresh strawberries, blueberries, and blackberries works best. Raspberries or frozen berries can be used instead.
- Cornstarch: thickens the filling so it doesn’t run.
- Lemon: zest adds brightness to the shortbread; juice seasons the berry filling.
- Granulated sugar: cane, brown, or coconut sugar can substitute.
- Jam or jelly: a thin brush of jam over the baked crust helps prevent the filling from soaking through.
Tips for using frozen berries:
- Add the fruit frozen, not thawed.
- Cut larger berries into smaller pieces so sizes are uniform.
- Increase the cornstarch by 1 tablespoon to account for extra liquid from frozen fruit.
Step-by-step Instructions
Begin by making the shortbread crust. After it bakes and cools slightly, add the berry filling and top with crumbled shortbread. Finish baking until set.

Step 1: Shortbread Cookie Crust
Preheat the oven to 350°F. Combine flour, powdered sugar, lemon zest, and salt in a bowl. Stir in melted butter and vanilla until a soft dough forms. Reserve about one-third of the dough for the topping, and press the remaining dough evenly into a parchment-lined 9×13-inch pan. Dock with a fork and bake 15–17 minutes, until the top no longer looks wet and the edges are set.

Step 2: Mix the Berries
Trim and cut larger berries to match the size of the blueberries. Toss the fruit with cornstarch, granulated sugar, and lemon juice until evenly coated. A suggested ratio is 2.5 cups strawberries, 1 cup blueberries, and 1 cup blackberries.

Step 3: Glaze the Crust and Fill
When the crust comes out of the oven, brush it lightly with a teaspoon of jam or jelly. Let it cool briefly, then spread the berry mixture in an even layer over the crust. Crumble the reserved shortbread dough over the top and, if you like, sprinkle a little extra granulated sugar. Increase oven temperature to 375°F and bake 30–35 minutes, until the filling bubbles and the topping is golden.
Step 4: Cool and Slice
Allow the bars to cool so the filling can set before slicing. After 20–30 minutes the bars can be cut into squares and removed from the pan. Serve at room temperature or slightly warm.

FAQs
Because the filling is made with fresh fruit, the bars are best within 2–3 days. Store in the refrigerator if you need to keep them longer.
Yes. Freeze individual squares or the whole pan wrapped tightly for up to 3 months. Thaw in the refrigerator overnight before serving.
Yes. Other berries or chopped stone fruits will work well; adjust sugar and cornstarch as needed depending on sweetness and juiciness.
No — brushing jam and adding the filling while the crust is still slightly warm is fine. Allow the finished bars to cool so the filling sets before slicing.

If you love this recipe, please leave a rating or a comment to share your experience with other home cooks. I hope you enjoy — happy eating!

Berry Crumble Bars
Ingredients
Shortbread Crust + Crumble
- 470 grams all-purpose flour
- 150 grams powdered sugar
- 1 teaspoon lemon zest
- 1/4 teaspoon salt
- 12 ounces unsalted butter, melted
- 2 teaspoons vanilla extract
- 1 teaspoon jam or jelly (berry flavor preferred)
Berry Filling
- 4.5 cups berries (fresh or frozen)
- 85 grams granulated sugar
- 3 1/2 tablespoons cornstarch (*see notes for frozen)
- 2 tablespoons lemon juice
Instructions
Shortbread crust + crumble
- Preheat oven to 350°F. Combine flour, powdered sugar, lemon zest, and salt in a large bowl.
- Melt the butter and stir in vanilla extract.
- Pour the butter into the dry ingredients and stir until a soft dough forms.
- Remove two-thirds of the dough and press it into a parchment-lined 9×13-inch pan. Reserve the remaining dough in the refrigerator.
- Prick the dough with a fork and bake 15–17 minutes, until the top no longer appears wet and the edges look set.
- Remove from oven and brush the crust lightly with the teaspoon of jam. Set aside until ready to fill.
Berry Filling
- Increase oven temperature to 375°F. Chop large berries into small, uniform pieces.
- Combine fruit, granulated sugar, cornstarch, and lemon juice in a large bowl and toss until evenly coated.
- Spread the berries over the shortbread crust in an even layer. Break up the reserved shortbread dough and sprinkle it over the top.
- Optionally sprinkle extra granulated sugar and bake 30–35 minutes until the filling bubbles and the topping is golden.
- Let the bars cool so the filling sets, then slice into squares and serve.
Notes
Frozen berries: Use them straight from the freezer and ensure pieces are uniform. Add 1 tablespoon extra cornstarch.
Berry ratio: A preferred mix is 2.5 cups strawberries, 1 cup blueberries, and 1 cup blackberries.
Baking sheet: If using a shallow sheet, place foil or a tray underneath the pan to catch any bubbling overflow.
Nutrition
Let us know how it was!
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