Blueberry Crumble Blondies

Classic blueberry blondies get a twist into this blueberry crumble blondie! The perfectly chewy and fudgy batter is swirled with fresh blueberry jam and topped with a buttery crumb to taste just like blueberry crumble!

These blueberry blondies are seriously the best ever. If you are unfamiliar with a blondie, it essentially is a "blonde" brownie, meaning it has the same fudgy and chewy texture as a brownie but doesn't use any chocolate. 

I decided to use my strawberry lemon blondie recipe as the base for these blueberry blondies and they turned out PERFECT!

They are so easy to make and you don't even need a mixer to make them.

For more blueberry recipes, try Blueberry Crumb Cake, Blueberry Macarons, and Blueberry Strawberry Shortcake.

why these blueberry blondies work

• These bars are so easy to make and require mostly staple pantry ingredients.
• They taste just like blueberry crumble, but in brownie bar form!
• They are a perfect summer-time treat but can be enjoyed year-round because they use frozen berries.
• Serve them as a breakfast pastry or dessert for any occasion!

ingredient notes

Full ingredient measurements and instructions can be found in the recipe card below!

• Frozen wild blueberries: These blueberries are tiny and have so much more flavor than regular-sized or fresh blueberries!
• Brown sugar: Light brown sugar is preferred but can be substituted with dark brown sugar too.
• Corn starch: This is used to thicken the jam.

recipe instructions

Step 1: Combine the frozen wild blueberries, sugar, lemon juice, and lemon zest in a small pot. Cook over medium heat for 8-9 minutes or until the blueberries have released their bright juices and are bubbling.

Whisk together the water and corn starch, then pour it into the pot and cook for 1 minute longer. The jam should be super thick. Transfer it to a bowl to cool completely.

Step 2: Make the crumb by combining the melted butter, flour, granulated sugar, and brown sugar. It will mostly be one large lump of dough. Place the bowl in the freezer until ready to use, then use your hands to break the crumb up into smaller pieces.

Step 3: Whisk together the egg, egg yolk, vanilla, sugar, and brown sugar for 1 minute or until light and fluffy. Stream the melted butter into the bowl until combined. Finally, fold the flour, baking powder, and salt.

Step 4: Evenly spread the blondie batter into a parchment-lined square 8x8 baking pan. Spoon dollops of the cooled jam over the top of the batter, then use an offset spatula to evenly spread it around the top. It will mix in with some of the batter which is perfect!

Step 5: Sprinkle the crumb pieces and the extra blueberries on top, then bake them at 350 F/180 C for 28-30 minutes, or until the middle looks puffed up and the edges are golden brown. You can also insert a toothpick into the center and it should come out covered in moist crumbs.

expert baking tips

• Use a kitchen scale: Baking with a scale is faster, easier, and overall much more accurate than cup measurements.
• Use room temperature ingredients: Using room temperature ingredients creates a smooth, fully blended batter that will result in a uniform texture and even baking.
• Dark vs. light baking trays: Baking pans conduct heat differently depending on what color it is. If your pan is dark or black you should decrease the heat to 325 F/163 C.
• Cooking times may vary: All ovens are different, and your bars may bake quicker or take longer than the indicated baking time. I recommend always checking on them occasionally and testing for doneness!

faq's

more recipes you'll love

If you tried this or any other recipe on my website, please let me know how it went in the comments below, I love hearing from you! Also, please leave a star rating while you're there! You can also tag me on Instagram or Facebook so I can check it out!

Recipe 📖

5 from 9 votes

Rate this Recipe Print Recipe Pin Recipe

Blueberry Crumble Blondies

Classic blueberry blondies get a twist into this blueberry crumble blondie! The perfectly chewy and fudgy batter is swirled with fresh blueberry jam and topped with a buttery crumb to taste just like blueberry crumble!

Servings 9 servings

Prep 25 mins

Cook 28 mins

Total 53 mins

Course : Breakfast, Dessert

Cuisine : American

Author : Cambrea Gordon

Equipment

• square 8x8 baking pan

Need Metric Measurements?Use the button options below to toggle between US cups and Metric grams!

Ingredients 

US CustomaryMetric

 

1x2x3x

Blueberry Jam Filling

• 1 cup frozen small wild blueberries
• ¼ teaspoon lemon zest
• 1 teaspoon lemon juice
• 2 tablespoon granulated sugar
• 2 teaspoon corn starch
• 2 teaspoon water

Crumble

• ¼ cup all-purpose flour
• 1 tablespoon granulated sugar
• 1 tablespoon light brown sugar packed
• 2 tablespoon unsalted butter melted

Blondie Batter

• 1 large egg
• 1 large egg yolk
• ⅔ cup light brown sugar packed
• ¼ cup granulated sugar
• 1 teaspoon vanilla extract
• ½ cup unsalted butter melted
• 1 cup + 2 tbsp all-purpose flour
• ¼ teaspoon baking powder
• ½ teaspoon salt
• ¼ cup frozen small wild blueberries for the top

Instructions

• Line a square 8x8 baking pan with parchment paper and preheat the oven to 350 F/180 C.

Make the Jam

• Combine the frozen blueberries, lemon zest, lemon juice, and sugar in a small pot. Cook over medium heat for 8-9 minutes or until the berries start to release their juices and boil.
  1 cup frozen small wild blueberries, ¼ teaspoon lemon zest, 1 teaspoon lemon juice, 2 tablespoon granulated sugar
• Whisk together the cornstarch and water.
  2 teaspoon corn starch, 2 teaspoon water
• Pour the cornstarch slurry into the jam and cook for 1-2 minutes longer until the jam is super thick. Then transfer it to a bowl and set it aside to cool completely.

Make the Crumb

• In a small bowl, combine the flour, sugar, brown sugar, and melted butter. Place the bowl in the freezer to chill the crumb while you make the blondie batter. Before using, use your hands to break up the crumb into small peices.
  ¼ cup all-purpose flour, 1 tablespoon granulated sugar, 1 tablespoon light brown sugar, 2 tablespoon unsalted butter

Make the Batter

• In a medium bowl, whisk together the egg, egg yolk, vanilla, brown sugar and sugar until light and pale in color.
  1 large egg, 1 large egg yolk, ⅔ cup light brown sugar, ¼ cup granulated sugar, 1 teaspoon vanilla extract
• Whisk in the melted butter.
  ½ cup unsalted butter
• Fold in the flour, baking powder, and salt until just combined.
  1 cup + 2 tablespoon all-purpose flour, ¼ teaspoon baking powder, ½ teaspoon salt
• Evenly spread the batter into the prepared pan.
• Dollop the cooled blueberry jam on top of the batter and use a spatula to evenly spread it over the top. The jam will mix some with the batter which is okay!
• Sprinkle the crumb and the frozen blueberries on top.
  ¼ cup frozen small wild blueberries
• Bake for 28-30 minutes, or until the middle is puffy, the edges are golden brown, and a toothpick inserted into the center comes out with just a few moist crumbs.
• Let cool completely before cutting then enjoy!

Notes

Step by step process photos are provided above, in the body of this post.

• Use a kitchen scale: Baking with a scale is faster, easier, and overall much more accurate than cup measurements.
• Use room temperature ingredients: Using room temperature ingredients creates a smooth, fully blended batter that will result in a uniform texture and even baking.
• Dark vs. light baking trays: Baking pans conduct heat differently depending on what color it is. If your pan is dark or black you should decrease the heat to 325 F/163 C.
• Cooking times may vary: All ovens are different, and your bars may bake quicker or take longer than the indicated baking time. I recommend always checking on them occasionally and testing for doneness!
• Can I use regular frozen blueberries or fresh blueberries? This recipe does best with the frozen small wild blueberries. Fresh blueberries will take longer to cook down and the flavor overall isn't as strong!
• Storage: Once cool, store the cut bars in a bag or sealed container at room temperature for 3-4 days.
• Freezing: Store the cut bars in a sealed container or freezer bag for up to 1 month!

Nutrition

Serving: 1serving | Calories: 220kcal | Carbohydrates: 26g | Protein: 1g | Fat: 13g | Saturated Fat: 8g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 4g | Trans Fat: 1g | Cholesterol: 55mg | Sodium: 149mg | Potassium: 44mg | Fiber: 1g | Sugar: 24g | Vitamin A: 431IU | Vitamin C: 2mg | Calcium: 29mg | Iron: 1mg

The calorie information provided for the recipe is an estimate. The accuracy of the calories listed is not guaranteed.