Blueberry Crumble Bars
It doesn’t get better than an easy summer dessert! These Blueberry Crumble Bars are layers of buttery oatmeal crisp with a sweet, juicy blueberry filling. They’re perfectly portable so they’re great for picnics or potlucks!
My favorite berries are blueberries, hands down. They’re so versatile, and I enjoy them daily in recipes like my blueberry banana smoothie or blueberry overnight oats.
I especially love baking with them, and was toiling over whether to incorporate them into a galette or bars. I took a poll on my Instagram stories, and Blueberry Crumble Bars won by a landslide.
I definitely wasn’t disappointed, because I love any dessert that resembles fruit crisp!
Why you’ll love this recipe:
- These bars include a sweet, juicy blueberry filling with the freshness of lemon juice and zest, and a hearty, golden brown oatmeal crumble.
- This recipe is so easy to make, requires minimal prep, and is a great make ahead dessert.
- This recipe is everything you love about fruit crisp in a handy, portable dessert that’s perfect for picnics, BBQs and more.
- The bars are easily made gluten-free by substituting the all purpose flour with gluten-free 1 to 1 flour.
- Bars may be made dairy free by using melted coconut oil in place of the butter. See my raspberry rhubarb bars recipe for more information.
Recipe ingredients
The majority of the ingredients for this recipe are pantry staples, so you should already have them on hand.
Ingredient notes
- Old fashioned rolled oats. Quick oats may be used, but they don’t have the same hearty texture as rolled oats.
- Coconut sugar. Substitute with
- Unsalted butter. Salted butter may be used — just omit the sea salt to avoid an overly salty crumble.
- Blueberries. Fresh or frozen may be used. If using frozen, thaw slightly and blot dry with paper towels.
- Lemon zest and juice. If you don’t have a fresh lemon on hand, simply omit.
How to make this recipe
These blueberry crumble bars couldn’t be easier to make. The crumble comes together in under 10 minutes, and there’s no fruit to chop because we’re using blueberries.
Prepare the oatmeal crumble
1. Place the flour, oats, 1/3 cup sugar, cinnamon and salt in a medium bowl and stir well to combine.
2. Add the cold cubes of butter to the dry ingredients. Using a pastry cutter, fork or your hands, work the butter into the dry ingredients until the mixture resembles pea-sized crumbles.
Prepare the blueberry filling
3. Place the blueberries, sugar, lemon zest and juice, and cornstarch in a medium bowl and stir until combined.
Assemble and bake the bars
4. Press 2/3 of the crumble into the bottom of a parchment lined 8×8″ baking dish.
5. Pour the blueberry filling evenly over the the crumble.
6. Top the blueberries with the remaining crumble. Bake at 350 degrees for about 50 minutes until golden brown and bubbly. Cover with foil after about 30 minutes if the crumble is browning too quickly.
7. Remove from heat and cool completely on a wire rack for a minimum of 3 hours or overnight until set.
FAQs
What are crumble bars?
Crumble bars are basically fruit crisp or crumble in bar form. The crumble topping is used on the top and the bottom of the bars to provide a base, which makes these a great handheld or portable dessert.
The crumble topping is either a combination of oats and flour like this recipe, or flour only. I love the heartiness of the oats, but if you’d like to try a shortbread style crumble, see these Berry Crumble Bars by the Comfort of Cooking.
Can I make this recipe gluten-free?
Yes! Substitute the flour in the crumble with the same amount of your favorite gluten free 1 to 1 flour blend. I’ve also used half almond flour and half oat flour successfully.
Can I make this recipe vegan?
I use coconut oil in place of butter often in my crumble toppings. Simply substitute melted coconut oil for the butter, and stir until the dry ingredients have moistened.
Recipe notes:
- Store leftover blueberry crumble bars at room temperature for up to 3 days, or in the refrigerator for up to 1 week.
- The coconut sugar may be substituted with granulated or brown sugar.
- Make these bars gluten-free by substituting the all purpose flour with gluten-free 1 to 1 flour.
- These bars may be made dairy free by substituting the butter with melted coconut oil. Simply stir it right into the dry ingredients! See my raspberry crumble bars recipe for more information.
More blueberry recipes you’ll love:
Blueberry Crumble Bars
Ingredients
For the oatmeal crumble:
- 1 1/4 cups all purpose flour
- 1 1/4 cups old fashioned rolled oats
- 1/3 cup coconut sugar
- 1 teaspoon ground cinnamon
- 1/4 teaspoon sea salt
- 3/4 cup unsalted butter cold, cut into small cubes
For the filling:
- 3 cups blueberries about 1 1/2 pints
- 1/2 cup coconut sugar
- 1 tablespoon lemon zest
- 2 tablespoons fresh lemon juice
- 2 tablespoons cornstarch
Instructions
- Preheat the oven to 350 degrees. Line an 8x8" baking dish with parchment paper or foil. Place the flour, oats, 1/3 cup sugar, cinnamon and salt in a medium bowl and stir well to combine.
- Add the cold cubes of butter to the dry ingredients. Using a pastry cutter, fork or your hands, work the butter into the dry ingredients until the mixture resembles pea-sized crumbles.
- Place the blueberries, 1/2 cup sugar, lemon zest and juice, and cornstarch in a medium bowl and stir until combined.
- Press 2/3 of the oat crumble into the bottom of the prepared pan.
- Pour the blueberry mixture evenly over the crumble.
- Sprinkle the remaining 1/3 of the crumble over the blueberry mixture.
- Bake for about 50 minutes until the center is bubbly, covering with foil after 30 minutes if the crumble is browning too quickly. Cool the blueberry crumble bars completely on a wire rack for a minimum of 3 hours or overnight until set. Cut into bars and enjoy!
Notes
- The coconut sugar may be substituted with granulated or brown sugar.
- Make these bars gluten-free by substituting the all purpose flour with gluten-free 1 to 1 flour.
- These bars may be made dairy free by substituting the butter with melted coconut oil. Simply stir it right into the dry ingredients! See my raspberry crumble bars recipe for more information.
Nutrition
Nutrition is estimated using a food database and is only intended to be used as a guideline for informational purposes.
8 Comments on “Blueberry Crumble Bars”
You know I love a good crumble bar Marcie, and blueberries are so easy to work with. No chopping required! Need to try these when local blueberries are in season here later this summer!
Yes I do! 🙂 Thanks Leanne!
We love blueberries around here, so when they’re on sale in the summer, we always stock up!! These crumble bars look fantastic!! A perfect summer bar 🙂
I stock up in the summer too! Thanks Katherine!
Aww, great minds are thinking alike, Marcie! I was working on some crumble bars over the weekend. I used quince jam for mine though 🙂 These look so lovely, and I am a huge blueberry fan! Great to know I can use frozen blueberries as it is Winter here at the moment! 🙂
‘Tis the season for crumble bars right? And quince jam sounds like an amazing filling!
Could I use frozen blueberries and do I need to drain them after thawing?
Yes! Frozen blueberries will work fine, simply thaw them and blot them dry before using. If they’re not super sweet, you may want to add a bit more sugar if you like a sweeter dessert.