These blueberry crumble bars are one of my most popular recipes that I have shared on my Instagram recently! They are so delicious, tart, and sweet, and they are made with nutritious ingredients. They are made with almond flour and oats, so they are gluten free too. I hope you love them!

What you will need to make this recipe
Crust Ingredients
- almond flour: almond flour is basically just very finely ground almonds. It is a very popular ingredient and flour alternative right now, not only because of its nutritional value and the fact that it is gluten free, but also because it has an incredible nutty flavor that adds so much to every recipe.
- oats: rolled oats like these.
- baking powder
- maple syrup: you can also use another liquid sweetener like agave or honey. However, do not use granulated sugar because the liquid sweetener in this recipe acts as a binding agent as well as a sweetener. If you use regular sugar, the crust won't bind and stick together.
- coconut oil: make sure the coconut oil is melted or very softened before adding it to the recipe. You can microwave it for 20-30 seconds to soften it up.
- vanilla
- dash of salt
Filling Ingredients
- blueberries (I used frozen): fresh or frozen blueberries will work in this recipe. I used frozen because they are more affordable. Also, because we will be cooking and baking the blueberries, you won't really be able to tell the difference between fresh and frozen.
- lemon zest and lemon juice
- coconut sugar: I like using coconut sugar because of the unique flavor it has and because it has a lower glycemic index. However, you can use any type of granulated sugar that you have on hand. However, make sure you use granulated sugar and not a liquid one like maple syrup. Otherwise, the consistency of the blueberry filling will be too runny.
- vanilla
- cornstarch: the cornstarch acts a thickening agent. It thickens up the blueberry sauce and gives the filling its perfect texture. Many people use arrowroot powder instead of cornstarch, but I have not experimented with it in this specific recipe, so i cannot say if this will work.
I also had a reader on Instagram message me to ask exactly what cornstarch is. This was a great question to point out, because cornstarch is called something different in some other countries. For example, in the UK, it is known as corn flour (something very different in the US). Just to clarify what I mean for readers that live outside of the US, here is a link of the type of cornstarch I am talking about. It is white, very fine, and starchy. This article explains the difference.
How to make the blueberry crumble bars
Start by making the crust. In a large bowl, combine the almond flour, oats, baking powder, maple, oil, vanilla, and salt. Mix them well.
Line the bottom of a 9 x 9 inch baking dish with parchment paper and grease it lightly with some coconut oil.
Then add the crust to the pan, but save about ½ cup of the mixture for the top layer.
Use a spatula or your fingers to pat down the crust until you have a tightly packed, even layer.
Now it's time to make your filling. To a pan, add the blueberries, lemon zest, lemon juice, coconut sugar, and vanilla.
Cook them over medium heat and use a potato masher to mash up the blueberries as best as you can. It doesn't have to be perfect but just enough to that they release their juices.
Cook the blueberry mixture for 3-4 minutes, then add in the cornstarch. Stir everything together for another minute, then remove from heat.
Pour the blueberry filling on top of the layer of crust. Use a spatula to make sure it's even.
Crumble the remaining ½ cup of crust on top of the blueberries.
Bake the bars for 30-35 minutes at 400F/ 200C.
Remove from the oven and give the bars plenty of time to cool so that the blueberry filling can set.
I sliced mine into smaller squares and made 16 bars with this recipe. Store it in the fridge for 5-6 days.
If you liked this recipe, you might also like these other delicious fruit desserts:
Blueberry Crumble Bars (Vegan & GF)
Equipment
- baking pan
- sauce pan
Ingredients
Crust Ingredients
- 1 cup almond flour
- 1 ½ cup oats
- 1 teaspoon baking powder
- ½ cup maple syrup
- ¼ cup coconut oil
- ½ teaspoon vanilla
- dash of salt
Filling Ingredients
- 2 cups blueberries I used frozen
- 1 tablespoon lemon zest
- 1 tablespoon lemon juice
- ⅓ cup coconut sugar
- ½ teaspoon vanilla
- 3 tablespoon cornstarch
Instructions
- Start by making the crust. In a large bowl, combine the almond flour, oats, baking powder, maple, oil, vanilla, and salt. Mix them well.
- Line the bottom of a 9 x 9 inch baking dish with parchment paper and grease it lightly with some coconut oil.
- Then add the crust to the pan, but save about ½ cup of the mixture for the top layer.
- Use a spatula or your fingers to pat down the crust until you have a tightly packed, even layer.
- Now it's time to make your filling. To a pan, add the blueberries, lemon zest, lemon juice, coconut sugar, and vanilla.
- Cook them over medium heat and use a potato masher to mash up the blueberries as best as you can. It doesn't have to be perfect but just enough to that they release their juices.
- Cook the blueberry mixture for 3-4 minutes, then add in the cornstarch. Stir everything together for another minute, then remove from heat.
- Pour the blueberry filling on top of the layer of crust. Use a spatula to make sure it's even.
- Crumble the remaining ½ cup of crust on top of the blueberries.
- Bake the bars for 30-35 minutes at 400*F.
- Remove from the oven and give the bars plenty of time to cool so that the blueberry filling can set.
- I sliced mine into smaller squares and made 16 bars with this recipe. Store it in the fridge for 5-6 days💙
Video
Nutrition
What if I don't have almond flour or I have a nut allergy?
You can substrate the almond flour for oat flour, whole wheat flour, or all purpose flour.
How should I store the blueberry bars?
Store them in the refrigerator in an airtight container.
How long will these be good for?
They last about 5-6 days in the fridge.
Tanya Musselman
Absolutely delicious!!! 30 min was too long for my oven, so I reduced the time.
Gaby Dimova
Sooo happy to hear that you liked them! 🙂