Mixed Berry Oatmeal Crumble Bars

9 Bars
1 hr 5 min

These easy, mixed berry oatmeal crumble bars have a brown butter oat crust, a triple berry filling and topped with more crumble topping that’s baked until golden and bubbly for the perfect summer dessert!

These berry crumble bars are my favorite way to use up those leftover summer berries laying in my fridge.

The bars make it so easy to just grab and go or heat and serve with ice cream.

Either way, they’re delicious and the perfect way to top off a hot summer night orrrr start a bright summer day with ;).

Mixed berry oatmeal crumble bars use strawberries, blueberries and raspberries that get baked with a brown butter shortbread-like crust.

I mean really, what’s not to love here?!

Buttery + Sweet + Tart + Crunchy + Gooey= dessert heaven!!!

Mixed Berry Oatmeal Crumble Bars
Recipe details
  • 9  Bars
  • Prep time: 15 Minutes Cook time: 50 Minutes Total time: 1 hr 5 min
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For the base layer & crumble topping
  • 1/2 cup butter, unsalted
  • 1 cup all-purpose flour
  • 3/4 cup old-fashioned rolled oats (not quick or instant)
  • 1/2 cup granulated sugar
  • 1/4 cup brown sugar, packed
  • 1 teaspoon ground cinnamon
  • 1/4 teaspoon ground ginger
  • 1/4 teaspoon salt
  • 1 egg yolk
For the mixed berry layer
  • 2 cups fresh mixed berries (blueberry, strawberry, raspberry)
  • 1/4 cup granulated sugar
  • 2 teaspoons cornstarch
  • juice of 1/2 lemon (about 2 tablespoons)
  • 1/2 teaspoon vanilla extract
  • pinch of salt
For the base layer & crumble topping
Preheat oven to 350 F. Line an 8x8" baking pan with parchment paper and spray with non-stick cooking spray.
Melt butter in small saucepan over medium heat. Continue melting until foamy; once it starts to brown and smell nutty remove from heat and set aside.
In medium mixing bowl, whisk together flour, oats, 1/2 cup granulated sugar, light brown sugar, ground cinnamon, ginger and pinch of salt.
Stir in browned butter, and 1 egg yolk. Continuing stirring until mixture is fully combined (if you squeeze it in your hand, it should hold its shape)
Reserve 1 cup of the crumble and set aside. With the remaining mixture, press into the bottom of the prepared pan.
For the mixed berry layer
In medium mixing bowl, combine berries, granulated sugar, cornstarch, lemon juice, vanilla extract and a pinch of salt in a medium bowl.
Spoon berries over the pressed base layer.
Top with the remaining 1 cup of oatmeal crumble that you previously set aside.
Bake at 350 degrees for 45-50 minutes or until you see the berries bubbling and the top golden brown.
Remove from oven, transfer to a wire rack and let cool completely before cutting into.
  • If using frozen berries, reduce lemon juice to 1 tbsp and increase cooking time to 55-60 minutes.
  • Bars can be stored in an airtight container up to 2 days or refrigerated for up to 1 week or frozen for up to 3 months.
Wine a Little Cook a Lot
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