Triple Berry Oat Crumb Bars

Triple Berry Oat Crumb Bars

This simple recipe for triple berry crumb bars is a great way to take a classic summer crumble on the go. Just as sweet and delicious as a classic fruit crisp or crumble, these oat crumb bars have a sturdy oat crust that makes them easy to transport wherever your summer adventures take you! They’re perfect for everything from picnics to cookouts.

Triple Berry Oat Crumb Bars

These berry oat crumb bars were made with a mix of blueberries, raspberries, and blackberries. Use the same combination or whichever berries you have on hand! If you’d like to use frozen berries, allow fruit to thaw completely in a colander so that excess juices drain as the fruit thaws.


Makes: 16 servings

  • 2 1/2 cups old fashioned rolled oats
  • 1 cup all-purpose flour
  • 1 cup brown sugar (packed)
  • 1 teaspoon sea salt
  • 16 tablespoons cold unsalted butter, rough chopped

  • 14 ounces (about 2 1/2 cups) fresh berries (I used a mix of raspberry, blueberry, and blackberry)
  • 6 tablespoons sugar
  • 2 tablespoons cornstarch
  • Zest of 1 lemon
  • Pinch sea salt


Preheat oven to 350 degrees F. Line an 8 x 8-inch square baking pan with parchment and butter the sides.

In a small bowl, toss to combine berries, sugar, cornstarch, zest, and sea salt. Set aside while you prep the other ingredients.

Triple Berry Oat Crumb Bars

To make the oat crumble, pulse to combine 2 cups oats until they have a sandy texture. Add flour, sugar, and sea salt, and pulse. Add butter; pulse several times to fully incorporate. Add remaining 1/2 cup oats and pulse 2 times.

Reserve 1 cup of the oat crumble mixture. With your fingers, roll reserved oat mixture into 1/2-inch clumps and spread on a small plate or rimmed baking sheet and chill in freezer 20 minutes.

Triple Berry Oat Crumb Bars

Meanwhile, press the remaining oat mixture into prepared baking pan, using the flat bottom of a measuring cup or glass to press crust firmly into place.

Triple Berry Oat Crumb Bars

Spoon fruit and any juices over bottom crust. Top with chilled topping.

Triple Berry Oat Crumb Bars

Bake until topping is golden and fruit filling is bubbling, 55 – 65 minutes. Cool 3 hours and then chill completely in the fridge before slicing. (If you’d like to slice into it sooner, the crumb bars will be delicious, but have more of a soft fruit crisp-like texture.)

With a large, sharp knife, slice into 16 (2-inch) bars, serve, and enjoy! Leftover bars can be kept covered in the fridge for up to 3 days.

Triple Berry Oat Crumb Bars Triple Berry Oat Crumb Bars