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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.
Gluten Free Blueberry Oat Bars Recipe
Ingredients
For the crumble
- 8 tablespoons (112 g) unsalted butter, melted and cooled
- ½ cup (70 g) all purpose gluten free flour blend, (I used Better Batter; please click thru for full info on appropriate blends)
- ¼ teaspoon xanthan gum, (omit if your blend already contains it)
- 1 cup (100 g) old fashioned rolled oats, (See Recipe Notes)
- ¼ cup (50 g) granulated sugar
- ⅓ cup (73 g) packed light brown sugar
- ⅛ teaspoon kosher salt
For the crust
- 1 cup (140 g) all purpose gluten free flour blend, (I used Better Batter; please click thru for full info on appropriate blends)
- ½ teaspoon xanthan gum, (omit if your blend already contains it)
- ¾ cup (90 g) oat flour, (See Recipe Notes)
- ⅛ teaspoon kosher salt
- ¼ teaspoon baking powder
- ½ cup (100 g) granulated sugar
- ¼ cup (25 g) old-fashioned rolled oats
- 6 tablespoons (84 g) unsalted butter, melted and cooled
- 1 (50 g (weighed out of shell)) egg, at room temperature, beaten
- 1 to 2 tablespoons lukewarm water
For the fruit layer
- 2 cups fresh blueberries, (about 12 ounces) rinsed and patted dry
- 2 tablespoons (24 g) granulated sugar
- 2 tablespoons (15 g) oat flour, (See Recipe Notes)
- ⅛ teaspoon kosher salt
Instructions
- Preheat your oven to 325°F. Grease a 9-inch square baking pan, and line with crisscrossed sheets of unbleached parchment paper to make it easy to lift the bars out of the pan after baking.
Make the crumble topping
- Combine all of the topping ingredients (8 tablespoons butter, 1/2 cup all purpose flour and xanthan gum, rolled oats, granulated and brown sugars, and salt), and blend with a fork until well-combined.
- Place in the refrigerator to chill until ready to use.
Make the crust
- In a large bowl, place the all purpose flour, xanthan gum, oat flour, salt, baking powder and granulated sugar, and whisk to combine well. Add the oats, and mix to combine.
- Create a well in the center of the dry ingredients, and add the butter, egg and 1 tablespoon water, and mix to combine.
- The dough will be a bit dry, and you will have to knead it with your hands to get it to come together. If necessary for the dough to hold together, add a second tablespoon of water, 1 teaspoon at a time.
- Transfer the dough to the prepared baking pan, and press firmly into an even layer on the bottom of the pan.
- Cover with another sheet of unbleached parchment paper and smooth out the dough by pressing it down evenly.
- Place the pan in the center of the preheated oven and bake for 7 to 10 minutes or until it appears set. It will lose some of its shine.
Make the fruit layer and assemble
- While the crust is parbaking, in a small bowl, place the blueberries, granulated sugar, oat flour, and salt, and toss to combine.
- After the crust is done parbaking, remove the pan from the oven and spread the blueberries out on top of the crust in a single, even layer.
- Remove the crumble topping from the refrigerator and fluff it with a fork to break it up into irregular pieces.
- Sprinkle the crumble topping in an even layer on top of the blueberries, and press gently to help it adhere to the blueberries in the filling.
- Return the pan to the oven, and bake until the crust is beginning to brown around the edges, a toothpick inserted into it comes out clean and the crumb topping is lightly golden brown (about 15 minutes).
- Remove the pan from the oven and allow to cool completely in the baking pan before lifting the bars out of the pan with the parchment paper.
- Slice into 12 equal pieces. Store each bar for later use wrapped separately, in the refrigerator or freezer.
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Notes
For oat flour, just grind oats into a fine powder in a blender. It doesn't need to be finely ground. To make the crumble recipe without oats at all, eliminate the oats and 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). For the fruit layer, replace the oat flour with 1 tablespoon (9 grams) cornstarch.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Sound good. I’m wondering I’d an apple like Granny Smith which usually holds its shape even baked would work if cut into blueberry size chunks. When it came to bars apple was always my favorite, followed by pumpkin.
I definitely would not recommend that, Karla. Apple is fibrous and takes much longer to bake until tender. I only recommend berries. I have lots of apple recipes, though.
I had the kids whip these up last night for breakfast this morning — delicious!
For my very first post :D … I would like to say how lovely these bars sound and look. How ever I have yet to find gluten free oats here in New Zealand. Maybe I will try with quinoa flakes (??). I know it wont be the same as your yummy original bars but I’m not sure I can wait for gluten free oats to be available here! I’d also like to say thank you, Nicole, for your lovely books and site. I have two of your books and have been looking forward to purchasing your GFOAS Bakes Bread since before it’s release!! But the time I has finally arrived for me to order it! Now I just have to wait for it to arrive. Thanks again hun!
I made this last Friday, and they tasted amazing. Everyone loved them! I even managed to source some gluten free oats!! Bonus!!
Yet another post that I want to make IMMEDIATELY. And I got a much needed dose of humor… never eaten them, made from picture. Love. Off to raid my kitchen.
Hi Nicole, I have recently discovered your blog here in Australia and just love it. Prior to going GF 18 months ago I was an avid cook (especially loving baking) but have really struggled since then. Your blog has inspired me again and everything I have cooked from it has really impressed my friends and family – love it. I just ordered your baking cook book and I am impatiently waiting for it to arrive. I cannot wait to try this recipe. Thanks for the inspiration.
Thanks so much for the nice note, Nici. I’m so glad you’re feeling hopeful and inspired to bake again. I promise it gets better and better. Over time, we’ll get you everything back that you miss. Promise. :)
Wow, I have every ingredient on hand, including local blueberries I froze last summer. I was planning on trying my hand at starting your pizza dough tonight (my copy of GFOASSBB already has a broken spine and a ton of highlights and post-it flags) but I may try this instead. How wet did the final bars turn out? Do you think it would work in smaller portions, say in jumbo silicone cupcake cups? I would use a tart tamper to get the crust flat and adjust the cooking time, of course, but I prefer making things in smaller sizes when possible (more caramelized edges! less chance of eating the whole pan!)
I honestly don’t know if they would work as individual cakes, Allison. They really are very much a bar cookie. I’d bake them in a pan, cut them up, and then wrap each individually. They store well in the refrig, or in the freezer.
Perfect …I love oat bars and even have all the ingredients handy . I look forward to making these very soon . This afternoon is not out of the question .
Thanks Nicole for all you hard work in developing your recipes . I have all three of your books .
This afternoon sounds like the perfect time, Sheree! And thank you so much for supporting me by buying the books. That means so much!
I’ve never seen these at our local joint(s) — but then I’m not really looking anymore because I know I can’t have it. and YES – your next cookbook is going to be AWESOME. I don’t know how I’ll handle the wait! :)
Can I omit the xantham gum? I really don’t like the taste of it and can’t eat items that contain it. Thanks! Also, do you have a Sweet Tomatoes or Souplantation near you? They currently have an amazing gluten free coconut muffin that I am dying to try to recreate but have no idea where to start! Do you have any recipes for coconut muffins? Thanks!!
I haven’t tried this recipe without xanthan gum, Meghan, but I believe it would fall apart. I would not omit it. I have never heard of Sweet Tomatoes or Souplantation. Sorry! I do have a recipe for coconut cupcakes on the blog. Just use the search function!
Thanks I will search for it now! I am fairly new to gluten free and just learning all the ins and outs. Are there any substitutions for xantham gum?
Yum! I cannot WAIT for this new cookbook!! My hubby was so excited about the chalupas! LOL! He’s started sending my pictures of your posts before I even get to them in the morning!
Now I hate to be “that guy” but….do you think I could get away with frozen blueberries? Just curious.
Your GFF,
John L
Oh, John, you have swooped and saved me so many times you’ll never ever be “that guy”! Yes you could totally use frozen berries (that’s the Alice Waters comment in the post ;). Don’t defrost them. They will “bleed” more than fresh, but the taste will still be fab.
P.S. I love that your husband sends you the photos. He’s just being careful. You might miss something otherwise. :)
Oh NO! I AM that guy!!! I didn’t read!! . I was so excited (and a bit distracted at work) that I went right to the ingredients and missed the actual blog post…. Boo. My apologies. That being said, I love all things blueberries so I will try these this weekend. Your “lighter” blueberry muffins are still a “regular” thing in our home. They. Are. So. Good.
Your GFF,
John L
Nope. Not that guy. You’ve got plenty in the bank to draw on. I consider it a fair withdrawal. ;)