Mixed Berry Crumb Bars
These easy, buttery berry crumb bars feature a golden crumb base, a vibrant mix of raspberries, blueberries, and blackberries, and a perfectly textured crumb topping. A delicious way to showcase summer fruit—perfect for gatherings or a cozy treat with coffee.
Ingredients
- All-purpose flour – 3 cups 360g, spooned and leveled
- Granulated sugar – 1½ cups 300g, divided (¾ cup for crumb, ¾ cup for filling)
- Baking powder – 1 teaspoon
- Salt – ¼ teaspoon fine table salt preferred
- Lemon – 1 whole zest and juice
- Cold unsalted butter – 1 cup 227g, cubed
- Large egg – 1 lightly whisked
- Cornstarch – 1 tablespoon
- Mixed berries – 5 cups 775g, fresh or frozen (raspberries, blueberries, blackberries)
Instructions
- Prepare the Oven and Pan
- Preheat oven to 375°F (190°C). Line a 9×13-inch baking pan with parchment paper, leaving an overhang for easy removal.
- Make the Crumb Mixture
- In a large bowl, whisk together flour, ¾ cup sugar, baking powder, salt, and lemon zest. Add cold butter and whisked egg. Use a pastry blender or fork to cut butter into the mixture until it resembles coarse crumbs with pea-sized pieces.
- Make the Berry Filling
- In a separate bowl, gently toss mixed berries with remaining ¾ cup sugar, cornstarch, and lemon juice. Stir carefully to avoid crushing the berries.
- Assemble the Bars
- Press half the crumb mixture firmly into the prepared pan to form the base. Spread berry mixture evenly over the base. Sprinkle remaining crumb mixture on top, covering the berries.
- Bake
- Bake for 45-50 minutes, or until the top is golden and berry juices bubble around the edges. Remove from oven and let cool completely at room temperature (2–3 hours), then chill for cleaner slices.
Notes
Butter: Keep butter cold for the best texture. Cube it in advance and return it to the fridge until ready to use. Frozen berries: Work great—don’t thaw. Increase cornstarch to 1 tbsp + 1 tsp. Baking time may increase by 5–10 minutes. Other fruit options: Use strawberries (chopped), peaches (diced), or apples. Increase cornstarch to 1½ tablespoons for juicier fruits. Storage: Store covered at room temperature for 2 days, or refrigerated for up to a week. Bars freeze well too. Serving tip: Delicious warm with vanilla ice cream or fresh whipped cream.
