These Blueberry Crumb Bars are so sweetly delicious. Made with fresh blueberries, a shortbread crust, and crunchy topping, you’ll love the textures and flavors of these awesome bars.
Table Of Contents
Recipe Details
Every summer, my family and I go blueberry picking in easter Washington. We come home with buckets of juicy ripe blueberries, so we make the best fresh berry dessert recipes. These amazing blueberry bars have become a staple in our home and I think you’re going to love them, too.
- TASTE: Buttery, fruity, and sweet, these Blueberry Oatmeal Bars taste heavenly. They have the most delicious buttery-sweet crumb on top.
- TEXTURE: The crust is made of a buttery shortbread, and the mix of juicy berries and crunchy topping is unbelievably good.
- TIME: These bars will take a little over an hour, but they can be made ahead and frozen for a snack or breakfast on the go.
- EASE: Even with three different components, this recipe is super easy to follow. It’s a simple treat with lots of flavor.
What You’ll Need
Ingredient Notes
- Unsalted butter– We use unsalted because we can better control the salt content this way. Make sure your butter is cold so it holds its shape in both the crust and crumb topping.
- Brown sugar– This richer, darker sugar adds a complex sweetness to the dessert, in the crust, topping, and blueberry filling.
- Vanilla extract– This adds a touch of vanilla that enhances the flavors of the blueberries and buttery topping.
- Fresh blueberries– These are best for this recipe. Frozen will work too, but you will need to add additional cornstarch to help control the extra moisture.
- Fresh lemon juice– Fresh juice is so much tastier than concentrate, so go with a fresh lemon for adding this ingredient to the mix.
- Old-fashioned oats– These oats give the crumble topping a delicious crumb that is a little chewy and lot yummy. Old fashioned oats have more chew than instant because the oats are larger in size.
Add-ins and Substitutions
- Substitute frozen blueberries- If you have only frozen berries, you can use extra cornstarch to thicken the juices in the blueberry mixture to avoid there being too much moisture, causing a soggy crust.
- Add other berries- For a fruitier bar, add raspberries, cherries (pitted), or blackberries. Just take out as many blueberries so the proportions stay the same.
- Add nuts- Try these with chopped walnuts, almonds, or pecans for more tasty texture and flavor.
How to Make Blueberry Crumb Bars
- Preheat your oven to 350 degrees F, and line a 9×13 inch baking pan with parchment paper.
- Make the dough for the crust. Combine the flour, melted butter, oats, brown sugar, granulated sugar, baking powder, salt, cinnamon, and vanilla in a medium bowl and mix them just until its crumbly but still holds together when pressed.
- Mold the crust. Press 2/3 of this mixture into the bottom of the prepared pan. I like to use ht bottom of a cup to press everything evenly.
- Make the filling. Add the blueberries, sugar, cornstarch, salt, lemon zest, and lemon juice to a large bowl and mix together.
- Add the filling to the crust. Spread the blueberry layer over the bottom dough crust.
Pro Tip: You can press the dough into the baking pan with your hands, but a spatula or the bottom of a cup works really well, too.
- Add the topping to the berries. Evenly sprinkle the remaining 1/3 of the oatmeal mixture on top of the berries.
- Bake. Bake it at 350 degrees Fahrenheit in a preheated oven for 40-45 minutes, or until the top turns golden brown. Let it cool to room temperature and refrigerate for at least one hour before slicing.
Recipe Tips
- Use fresh blueberries- To get the best flavor and juicy-jammy filling.
- Don’t skip the lemon zest- It has a bright flavor that elevates the bars to the next level.
- Don’t overmix the crumble- You want it crumbly and slightly chunky for the best crispy, crunchy texture.
FAQs
Yes, you can. However, frozen blueberries will have more water in them, so to avoid a soggy crust add an extra 1/2 to 1 Tbsp cornstarch to help absorb excess water and allow them to distribute evenly within the filling mixture.
It’s very easy to make this recipe gluten-free. All you need to do is substitute the all-purpose flour with gluten-free baking flour (such as Bob’s Red Mill Gluten-Free Baking Flour) and make sure that the old-fashioned oats are certified as gluten-free (otherwise there is a possibility of gluten in them because of cross-contamination during processing). That’s it!
These bars are absolutely delicious, with lots of fiber and vitamins from the fresh blueberries and oatmeal. But if you want to try a lighter version, you can make some changes to lower the sugar and incorporate healthier options, like using whole wheat flour, pure maple syrup in place of the sugar, or substituting applesauce or mashed banana for the butter.
Serving Suggestions
These Blueberry Crumb Bars are delicious and can be enjoyed as a sweet breakfast or dessert. Enjoy them with pancakes, eggs, fruity favorites, or smoothies.
- Pancakes: Enjoy these bars alongside Buttermilk Pancakes, Chocolate Pancakes, Blueberry Ricotta Pancakes, or a German Pancake (VIDEO).
- Eggs: Pair a blueberry bar with some Egg Bites, Eggs Benedict, Easy Poached Eggs with Caramelized Onions, or Egg Sandwiches.
- Fruity favorites: Try this recipe with some Creamy Fruit Salad, Fruit Kabobs, Berry Chantilly Cake, or Blueberry Crisp.
- Smoothies: Wash this tasty treat down with a smoothie, like this Tropical Smoothie, Mango Smoothie, Mandarin Banana Smoothie, or a Blueberry Smoothie Bowl.
Make This Recipe in Advance
Make ahead: To make these bars in advance, wrap them individually with plastic wrap once they have cooled and been cut. They can be stored in the refrigerator or freezer, depending on how long you want to keep them.
Storing: Wrap the blueberry oatmeal bars in plastic wrap to keep them from sticking together and place them in an airtight container in the fridge. They will last for about 3 days.
Freeze: To keep them longer, place the container in the freezer and they will stay fresh for up to 3 months.
More Yummy Fruit Desserts!
Full Recipe Instructions
Blueberry Crumb Bars
Equipment
- 1 9×13 baking pan
Ingredients
Ingredients for crust and topping
- 3 cups all-purpose flour
- 1 cups old-fashioned oats
- 1 cup light brown sugar packed
- ½ cup granulated sugar
- 1 tsp baking powder
- 1/2 tsp salt
- 1/8 tsp ground cinnamon
- 1 cup unsalted butter melted
- 2 tsp vanilla extract
For the Blueberry Filling
- 4 cups fresh blueberries
- 1/2 cup granulated sugar
- 1 Tbsp cornstarch
- 1/8 tsp salt
- 1 Tbsp lemon zest about 1 lemon
- 2 Tbsp fresh lemon juice
Instructions
- Preheat the oven to 350°F and line a 9×13 inch baking pan with parchment paper. In a large bowl, mix the flour, oats, brown sugar, granulated sugar, baking powder, salt and cinnamon.
- Stir in the melted butter and vanilla until crumbly.
- Press two-thirds of the oat mixture firmly into the bottom of the prepared pan. Reserve the remaining third of the crumb mixture for later.
- In a separate bowl, toss the blueberries, sugar, lemon juice, lemon zest, cornstarch, and salt until evenly coated.
- Spread the blueberry mixture over the bottom crust.
- Sprinkle the remaining oat mixture evenly over the blueberries.
- Bake for 40-45 minutes, or until the topping is golden brown and the blueberry filling is bubbling.
- Cool completely in the pan. Refrigerate for 1 hour before slicing for the cleanest bars. Cut into squares and serve.
Notes
- Use fresh blueberries- To get the best flavor and juicy-jammy filling.
- Don’t skip the lemon zest- It has a bright flavor that elevates the bars to the next level.
- Don’t overmix the crumble- You want it crumbly and slightly chunky for the best crispy, crunchy texture.
Nutrition
This recipe was originally posted on June 24, 2016, but it has been tweaked a bit since then.
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Marianne says
Can frozen blueberries be used?
Dina says
Yes, you can. However, frozen blueberries will have more water in them, so to avoid a soggy crust, thaw them first before using them. If you have to use them frozen, toss them in some flour to help absorb excess water and allow them to distribute evenly within the filling mixture. I hope that helps 🙂
Lily says
These taste AMAZING straight out the oven. I do want to try it with less sugar.
Dina says
I am so glad that you loved these blueberry oatmeal bars Lily! I have not tested them with less sugar. If you give it a try, let me know how they turn out!
Donna says
Do you have to use flax seed in this recipe? Is there a substitute for it or can I just leave it out?
Dina says
Hi Donna 🙂 You can just leave the flax seed out for these blueberry oatmeal bars. Let me know how this recipe turns out! 🙂
Velvet Lang says
Recipe is delicious – just the right amount of sweetness with fresh picked blueberries. Have you tried making it with frozen blueberries? If so, how does it turn out? Is there any adjustments needed to the recipe when using frozen blueberries?
Dina says
Thank you so much for the fantastic recipe feedback! You can definitely use frozen blueberries, just make sure to thaw and drain them before using.
Irina says
Can I use frozen blueberries?
simplyhomecooked says
Hi Irina, frozen blueberries will work too.
Tati says
Good idea overall; however, I am not sure that I would make these again without modifications. I thought there was way too much flour in this recipe, and they turned out quite dry. I would modify the flour content if I made them again. I was quite disappointed, and I bake a lot.
Natasha says
These were AMAZING! Not too sweet, yet full of flavor and not dry at all! I did add white chocolate drizzle on top for decor! I would recommend for anyone to give these yummy bars a try! 5 star for sure! Thanks Dina!
simplyhomecooked says
Natasha I’m so glad to hear the bars turned out well! Love the idea of adding a white chocolate drizzle!
Natasha says
Just made these and they are delicious! I would definitely recommend. I was worried it may be a little dry but the blueberries let out a bit of juice while baking that gives a great tangy complement to the streusel topping.
simplyhomecooked says
Thank you for taking the time to write such a nice review Natasha! You’re so sweet 🙂
Marina says
Love the blueberry hills restaurant!! And their blueberries are the best I ever had.
simplyhomecooked says
I couldn’t agree more Marina!