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These gluten free blueberry oat bars have a shortbread crust, simple fruit filling, and a crispy crumble topping.

Why this recipe works
Whether it's blueberry season or not, this recipe for Starbucks-style blueberry breakfast bars is a great breakfast alternative to granola bars. I believe that Starbucks calls them blueberry oat bars.
If you can't have oats, I have plenty of suggestions for how to make them oat-free.
The crust is like an oat-shortbread. It's buttery and kinda crumbly, with the slight chew of oats mixed in. The crumble topping has the perfect nubby, crisp-tender texture of a proper crumble topping.
The blueberries keep their shape even after baking, because the crust doesn't take long to bake. That means they don't melt into a silky sauce to be eaten with a spoon.

If you like granola bars, my classic mix-and-match granola bar recipe and granola strawberry bars are great options, too. If you'd rather have an oat bar without any fruit that has a smoother texture, try our square gluten free breakfast bars.
Can I make these fruit bars with frozen berries?
Yes, you can! Blueberries are one of the best fruits to buy frozen, since they're always sweet when they're frozen, never tart like out of season fresh berries often are. Frozen berries will leak a bit more than fresh ones, but even the frozen ones should hold their shape quite well.
There are two types of frozen blueberries: wild blueberries, which tend to be rather small, and standard blueberries, which look more like the berries you'd buy fresh in the grocery store. Here, I recommend the standard-size berries.
When baking with frozen berries, do not defrost them or they'll begin to lose their shape before you place them in the oven. Work with them frozen, and work quickly to assemble the rest of the recipe before you bake.

Alternate berry suggestions
Raspberries, fresh or frozen, would work really well here in this recipe. In fact, you could use a combination of blueberries and raspberries with great results.
Strawberries have more moisture than the other berries, so I can't be sure that the bars would hold together. If you do use strawberries, only use fresh so that you can slice them into chunks that are about the size of blueberries.
If you decide to try the recipe with strawberries, they'll definitely produce more moisture in the oven. Try adding 1 tablespoon of tapioca starch to the oat flour to help the liquid gel as the bars cook.
If you'd like to make gluten free breakfast bars without fruit at all, I recommend trying our gluten free oatmeal bars. They're even more portable than these breakfast bars, since they don't have any fruit.

Ingredients and substitutions
Dairy free
The only dairy in this recipe is butter, and you should be able to replace it in both the crust and the crumble topping with vegan butter. My favorite brands are Melt and Miyoko's Kitchen.
I really recommend against Earth Balance buttery sticks, especially for the crumble topping. Earth Balance has a lot of moisture in it, and the crumbles likely wouldn't hold their shape during baking.
Egg free
There's only 1 egg in this recipe, in the crust recipe. It acts as a binder. You should be able to replace it with a 1 “chia egg” (1 tablespoon ground white chia seeds + 1 tablespoon lukewarm water, mixed and allowed to gel).


Oat free
If you'd like to make these bars without oats at all,a few simple swaps and these gluten free breakfast bars will be oat-free and still hearty and tasty.
Typically, when I'm using a substitute for oats in their various forms, I replace oat flour with quinoa flakes and rolled oats with beaten rice. Here, since I've made both shortbread crusts and crumble toppings without oats entirely, it's even easier to make all parts of these bars without oats.
For the crumble recipe, increase the all purpose gluten free flour blend to 1 cup (140 grams).
For the crust, eliminate the oats and oat flour, and increase the all purpose gluten free flour blend to 1 cup + 2 tablespoons (158 grams). Otherwise, follow the recipe as written here, too.
For the fruit layer, replace the oat flour with 1 tablespoon (9 grams) cornstarch. If you can't have corn, try tapioca starch/flour.

















I cannot get this blueberry oat bar to open…it has disappeared .
help please…
The recipe and post are all here, Cricket. I’m not sure what to suggest. If you’re not seeing a video play, it’s because of an ad blocker, but the recipe is here.
can I use frozen blueberries? I have an overload of them and need to use them up!
thanks
Please see the text of the post under the heading “Can I make these breakfast bars with frozen berries?”
Just delicious. I ran short on blueberries so I used 1/2 cup coarsely chopped strawberries to make up the 2 cups needed. Would the difference in moisture be the reason why it took nearly a 1/2 hour more for the batter to all set up? When it finally did it was really delicious with the 2 types of berries. worth tinkering to try and get that topping to be crunchy, too.
Blueberries don’t have as much moisture as cut strawberries, which is why I wouldn’t ever recommend using them interchangeably. Glad you enjoyed the bars!
Easy to make. My kids love them. It’s nice finding great tasting gluten free items that are easy to make and don’t have the grainy texture that some recipes have.
So glad your kids loved the breakfast bars, Matt! That grainy texture is from gritty rice flour that is unfortunately very common in many if not most available gluten free flour blends. I know that it bothers some readers that I’m so specific in what flour blends I recommend and the ones I recommend against, but this is why!
Hi Nicole! Love your recipes. Have several of your books too. In this one – can I use quick cooking steel cut oats (I have lots I’d like to use up)?
That’s an interesting question, Melanie. I don’t think I’ve ever heard of quick-cooking steel cut oats. That seems oxymoronic. If they’re of similar texture to old fashioned rolled oats, and they’re able to be ground into a flour, then I don’t see why not?
Thanks Nicole for another great recipe. I made it successfully oat free and the blueberry and raspberry combination was a huge hit. Will be adding it to my list regularly for baking for lunch boxes. Thanks Victoria
That’s great to hear, Victoria! Those will be some happy kids. :)
That is a lot of butter and sugar! Any ideas for making this healthy?
That would be a completely different recipe. This isn’t a “healthy lifestyle” food blog, though, PJ.
Any chance you have a calorie count on these?
I don’t provide nutritional information, no, Jennifer. Feel free to plug it into an online calculator yourself! That’s all I would do anyway.