These Blueberry Crumble Bars feature a buttery shortbread crust, that’s full of warm gooey summer juicy blueberries, and a brown sugar oat crisp topping. Serve warm with a big scoop of vanilla ice cream and a drizzle of caramel sauce for a comforting summer-inspired dessert!
Being in the kitchen since I was young I know ere in North America, I know it’s summer when all the fresh berries come out.
The mornings are warm and beautiful and my local markets have many of my summer favorites, strawberries, raspberries and of course blueberries.
And since we are in the midst of blueberry season, I had to make my take on the quintessential summer dessert, Blueberry Crumble.
Blueberry Crumble is a flavorful, decadent dish that’s best when served warm with a drizzle of caramel sauce and a scoop of vanilla ice cream. Similar to blueberry cobbler; it’s really a combination of both. Blueberry Crumb bars takes the gooey blueberry pie filling and the buttery crumble of a cobbler for one luscious dessert.
And when placed on top of buttery crust, you have one portable summer-inspired dessert that will quickly become a favorite go-to warm weather dessert!
crumb topping ingredients
- unsalted butter
- light or dark brown sugar
- granulated sugar
- pure vanilla extract
- all-purpose flour
- baking powder
- salt
- old fashioned oats
Brown sugar: I used dark brown sugar in the crisp topping as I prefer that rich, deep, dark molasses flavor but if you prefer light brown sugar, feel free to use.
Butter: I prefer using unsalted butter but if you have salted butter just be sure to decrease your salt by ¼ tsp.
Blueberries: Use fresh or frozen blueberries. If you are using frozen be sure to thaw and strain first to avoid extra juice. They may also bleed into the cookie dough.
how to make crumble topping
STEP ONE: For the crust/topping: Using a handheld or stand mixer fitted with a paddle attachment, beat in large bowl the ¾ cup butter, ½ cup brown sugar and ¼ cup granulated sugar together on medium-high speed until combined, about 1 minute. Scrape down the sides and up the bottom of the bowl with a rubber spatula.
STEP TWO: add 1 tsp vanilla extract. Beat on medium-high speed until combined, about 30 seconds.
STEP THREE: Add the 1 cup of flour, 1 tsp baking powder, ¼ tsp salt, and 1 cup oats. Beat on medium speed until combined. Mixture will appear dry and be crumbly. You will have between 3 cups of crust/crumble mixture.
STEP FOUR: Lightly press a little more than half of crumble mixture into bottom of prepared baking pan. (You want a little more mixture for the crust than for the topping.) Bake for 12 minutes.
ingredients for blueberry layer
- Blueberries Fresh or Frozen
- water
- cornstarch
- sweetened condensed milk
sweetened condensed milk: NOT evaporated milk. Please do not try and replace sweetened condensed milk as it is the key ingredient. Use one 300ml can full-fat sweetened condensed milk. Do not use fat-free because the filling will not set.
how to make blueberry filling
STEP ONE: Add the 1½ cup blueberries, and 2 tbsp. water to a small sauce pan over medium heat. Stir occasionally, the blueberries will start to burst open and create a little sauce. Use your spoon to help squish them a bit. Bring to a slow boil.
STEP TWO: Stir the 1½ tsp cornstarch. Let continue to cook until the blueberry mixture has thickened enough to coat the back of a wooden spoon.
STEP THREE: Transfer to a small bowl to cool and thicken. Pour in 1 can of sweetened condensed milk, mixture will be thick. Pour and spread filling over pre-baked crust (while crust is hot). Sprinkle the remaining crust mixture on top.
STEP FOUR: Return bars to the oven and bake for 25-30 minutes or until edges are very lightly browned and appear set. Avoid over-baking. Remove from the oven and place the pan on a wire rack. Cool bars completely.
how to store
Cover leftover bars and store in airtight container in the refrigerator for up to 1 week.
can i freeze blueberry crumble bars?
Once the bars have completely cooled, place the 8×8 baking dish into the refrigerator to allow the filling to set. Once chilled, remove uncut crumble from pan; keeping parchment paper on. Wrap entire bake in plastic wrap then aluminum foil. Place in on a flat surface in freezer up to 1 month.
When ready to eat, thaw in the fridge over night. Reheat in oven at 350F for 10-15 minutes or until warmed through. Cut prior to serving.
can i use quick oats for the crisp topping?
While old fashioned oats work best, you can certainly use quick oats if that’s all you have on hand. Just be aware that the crisp topping might be more powdery (don’t reduce the flour though otherwise the crisp topping may turn out too greasy). Use a 1:1 swap when replacing quick oats for old fashioned.
bbq bakers tips and tricks
- 1½ cup Blueberries is approximately 1 quart.
- Room temperature butter is preferred however, if you cold butter or frozen you can leave it on the counter for as little as 15 minutes or heat a glass with hot water and place on top.
- Add some chopped nuts to your crisp topping like pecans or walnuts for more crunch!
- Serve warm with a scoop of vanilla ice cream that’s drizzled in caramel sauce
Next time you are looking for an afternoon snack these easy blueberry bars are a hit the first time. The combination of a generous layer of fresh blueberries on a buttery shortbread-like layer leaves you with a magnitude of welcomed different flavors.
more summer desserts to try
- Strawberry Rhubarb Bars
- Apple Crisp Bars
- Blueberry Rhubarb Crumble Cookies
- Brown Butter Apple Blondies
- Caramel Chocolate Apple Galette
Blueberry Crumble Bars
Ingredients
- ¾ cup unsalted butter room temperature
- ½ cup light or dark brown sugar
- ¼ cup granulated sugar
- 1 teaspoon pure vanilla extract
- 1 cup all-purpose flour
- 1 teaspoon baking powder
- ¼ teaspoon salt
- 1 cup old fashioned oats
Blueberry Filling
- 1½ cup Blueberries Fresh or Frozen
- 2 tablespoon water
- 1½ teaspoon cornstarch
- 1 can sweetened condensed milk 300ml
Instructions
- Preheat oven to 350°F (177°C). Line an 8-inch square pan with parchment paper.
- For the crust/topping: Using a handheld or stand mixer fitted with a paddle attachment, beat the ¾ cup butter, ½ cup brown sugar and ¼ cup granulated sugar together on medium-high speed until combined, about 1 minute. Scrape down the sides and up the bottom of the bowl with a rubber spatula and then add 1 tsp vanilla extract. Beat on medium-high speed until combined, about 30 seconds.
- Add the 1 cup of flour, 1 tsp baking powder, ¼ tsp salt, and 1 cup oats. Beat on medium speed until combined. Scrape down the sides and up the bottom of the bowl and beat again as needed to combine. Mixture will appear dry and be crumbly. You will have between 3 cups of crust/crumble mixture.
- Lightly press a little more than half of crumble mixture into bottom of prepared baking pan. (You want a little more mixture for the crust than for the topping.) Bake for 12 minutes.
Blueberry Filling
- Add the 1½ cup blueberries, and 2 tbsp. water to a small sauce pan over medium heat. Stir occasionally, the blueberries will start to burst open and create a little sauce. Use your spoon to help squish them a bit. Bring to a slow boil.
- Stir the 1½ tsp cornstarch. Let continue to cook until the jam has thickened enough to coat the back of a wooden spoon.
- Transfer to a small bowl to cool and thicken. Pour in 1 can of sweetened condensed milk, mixture will be thick. Pour and spread filling over pre-baked crust (while crust is hot). Sprinkle the remaining crumble mixture on top.
- Return bars to the oven and bake for 25-30 minutes or until edges are very lightly browned and appear set. Avoid over-baking. Remove from the oven and place the pan on a wire rack. Cool bars completely.
- Cover leftover bars and store in airtight container in the refrigerator for up to 1 week.
Notes
- Make Ahead: You can make the crust/topping dough and blueberry filling (separately) and chill it in the refrigerator for up to 2-3 days. Allow to come to room temperature then continue with preheating the oven.
- Freezing Instructions: Obviously. Once the bars have completely cooled, place the 8×8 baking dish into the refrigerator to allow the filling to set. Once chilled, remove uncut crumble from pan; keeping parchment paper on. Wrap entire bake in plastic wrap then aluminum foil. Place in on a flat surface in freezer up to 1 month. Thaw overnight in the refrigerator and bring to room temperature before enjoying.
- Sweetened Condensed Milk: NOT evaporated milk. Please do not try and replace sweetened condensed milk as it is the key ingredient. Use one 300ml can full-fat sweetened condensed milk. Do not use fat-free because the filling will not set.
- Frozen Fruit – Use fresh or frozen blueberries. If you are using frozen be sure to thaw and strain first to avoid extra juice. They may also bleed into the cookie dough.