Blueberry raspberry crumble bars make the perfect refreshing summer treat. While they’re a dessert, of course, they’re light and airy enough to enjoy guilt-free! This recipe will make enough for a family, but we won’t judge if you decide to eat the whole pan. These scrumptious crumble bars have the perfect ratio of sweetness and tartness, taking your taste buds on an exciting culinary adventure.

You probably have a lot of the basic baking ingredients stuffed away in your cupboards somewhere. If not, it just takes a quick trip to the store to gather what you’ll need. So, let’s get to the good stuff! We’ll share our secret on making the best blueberry raspberry crumble bars you’ll ever taste.

How to Make Blueberry Raspberry Crumble Bars

crumble bars

Kitchen gadgets you’ll need:

  • Large mixing bowl (as usual)
  • Smaller bowl
  • Whisk
  • Large spoon
  • Large baking sheet
  • Parchment paper
  • Large cooking pot
  • Measuring cups and spoons
  • Knife
  • Aluminum foil
  • Rolling pin or coffee mug

Ingredients for bottom and top crumble layer:

  • 4 cups rolled oats
  • 4 cups all-purpose flour
  • 1 tbsp baking powder
  • 1 1/2 cup coconut sugar
  • 1/2 tsp salt
  • 1 1/2 cup coconut oil
  • 1 tbsp vanilla

Ingredients for blueberry raspberry filling:

  • 1 cup frozen raspberries
  • 1/2 cup brown sugar
  • 3 tbsp lemon juice
  • 1 cup frozen blueberries
  • 1 tbsp corn starch
  • Fresh raspberries and blueberries

blueberry raspberry bars

Directions for making the crumble layers:

  1. You know the drill for these recipes by now, right? We thought so! Have your large mixing bowl handy. Pour in the oats, all-purpose flour, baking powder, coconut sugar, and salt.
  2. Whisk the ingredients until fully combined. Next, pour in the coconut oil and vanilla, using the large spoon to blend them into the oats.
  3. Once they’re thoroughly combined, use your hand to mix the ingredients further. The texture should resemble crumbly oats.
  4. Now, grab your baking sheet and line it with parchment paper. Pour 2/3 of the mixture onto the pan, and save the rest for later.
  5. Use your hand to spread the mixture evenly across the pan, pressing down firmly along the edges. Next, use a coffee mug or rolling pin to roll the oats. This ensures they’ll bake evenly and won’t fall apart on you.

Directions for making the blueberry and raspberry fillings:

  1. Set that aside and get out your cooking pot. Pour in the frozen raspberries and turn the heat on medium-low. Stir occasionally.
  2. Once they come to a slight boil, pour 1/4 of the brown sugar and mix it in.
  3. Next, mix in 2 tbsp of the lemon juice. When the raspberries have cooked down to a sauce-like, slightly chunky texture, remove from the heat.
  4. In a small bowl, pour in your frozen blueberries. Mix in the remaining 1/3 cup of brown sugar, 1 tbsp lemon juice, and corn starch. Use a small spoon to blend the ingredients, mashing down the blueberries in the process.

Putting it all together:

  1. So, now that you have your two fillings for the blueberry raspberry crumble bars cut down the middle of the crumble layer with your knife.
  2. Next, take a piece of aluminum foil and fold it up lengthwise. Use this to separate the blueberry and raspberry fillings where you made the cut down the middle.
  3. Now, spoon the raspberry filling onto one side of the pan. Take a container of fresh raspberries and place them uniformly throughout the filling. This will add some texture to the crumble bars.
  4. Repeat this step with the blueberry filling on the other side. Place fresh blueberries on top of the filling, about three per row. If you want to be exact, we used about 18 blueberries total.
  5. Finally, sprinkle the rest of the oat mixture on both the raspberry and blueberry fillings. Pat it down with your hand, then bake the crumble bars at 350 degrees F for 40-45 minutes.
  6. Now, remove the parchment paper and aluminum foil. Cut the bars lengthwise on each side, then make three cuts widthwise. You should end up with 8 crumble bars of each filling.

We hope you enjoy these delectable crumble bars! They’re gooey, crunchy, sweet, and tart at the same time, giving them the perfect texture and flavor.

A few more tips:

To ensure your bars turn out amazing, here are a few extra pro tips we gathered along the way:

  • Want an extra crunchy crust and topping? Add about 1/2-1 cup of butter to the recipe! You’ll want to make sure it’s softened first, so it’s easier to mix in. Not only will the addition of the butter provide more texture, but it will also give the crumble bars a richer flavor as well.
  • If you’re a big berry fan, feel free to add other types of berries like blackberries or strawberries!
  • Chill the bars for 30 minutes to an hour before cutting them. It will make the slices much cleaner and easier to cut.
  • Serve with vanilla ice cream or whipped cream on top! (You can also eat them for breakfast since they have fruit, but you may want to opt-out of the ice cream in this case).
  • Freeze or store in the fridge if you have leftovers. Keep in mind that the crumbly texture won’t keep as well in the freezer. However, the crumble bars will still taste amazing!

Final thoughts on these amazingly delicious blueberry raspberry crumble bars.

If you’re drooling after reading this recipe, we don’t blame you. Maybe it will give you more motivation to get into the kitchen and start baking! It doesn’t seem all that appealing to stand over a hot oven on hot summer days. However, these bars will help cool you off with the refreshing berry layer, so it’s totally worth the effort, in our opinion.

Many variations of crumble bars exist, but there’s none quite as revitalizing as these berry crumble bars. Desserts get a bad rap these days because they’re usually heavy and filling, but this recipe is just the opposite. Ready to try them out for yourself? We thought so!