Description

These buttery mixed berry crumble bars are layered with juicy fruit and golden oat topping—perfect for a sweet snack, summer dessert, or picnic treat.

Ingredients

For the Base & Crumble Topping:

2½ cups all-purpose flour

1½ cups old-fashioned oats

1 cup granulated sugar

½ cup brown sugar

1 tsp ground cinnamon

1 cup melted butter (preferably salted)

1 large egg

For the Berry Layer:

4½ cups mixed berries (fresh or frozen strawberries, raspberries, blueberries, blackberries)

½ cup granulated sugar

2 Tbsp lemon juice (use 1 Tbsp if berries are frozen)

3 Tbsp cornstarch

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Instructions

Preheat oven to 350 °F (175 °C). Line a 9×13″ baking pan with parchment paper, leaving a bit of overhang for easy removal.

In a large bowl, mix flour, oats, granulated sugar, brown sugar, and cinnamon. Stir in melted butter and egg until crumbly and well combined.

Press about ¾ of the mixture into the prepared pan to form a firm base. Reserve the rest for topping.

In another bowl, toss berries with sugar, lemon juice, and cornstarch. If overly juicy, strain a bit of the liquid.

Spread berry mixture evenly over the crust. Sprinkle reserved crumble mixture in clusters over the top.

Bake for 45–50 minutes (up to 60 with frozen berries), until the top is golden and the filling is bubbling.

Cool at room temperature for 30 minutes, then refrigerate for 3–4 hours (or longer) to fully set. Slice into bars once chilled.

Notes

Frozen berries work great—just don’t thaw before using.

Customize with your favorite berry mix or even a layer of jam for more intense flavor.

Almond flour or baking powder can be added to the base for a cakier texture.

Try adding ginger or extra cinnamon for a warmer, spiced flavor.

Store in the fridge for up to 4 days or freeze for up to 3 months.

Prep Time: 15 minutes
Cook Time: 45–50 minutes
Category: Dessert, Snack
Method: Baking
Cuisine: American