These gluten-free vegan blueberry crumb bars have quickly become a favorite in our house! I mean… with a oat crumble topping and a lemon glaze how could you really go wrong?
I love these for entertaining guests during the summer or just for an easy dessert on the weekends. They’re so easy to make gluten-free and I’ve made this version dairy-free and vegan, too!
I like how adaptable these are depending on your food restrictions. Don’t need them to be dairy-free? Use regular butter. Need them to be vegan? Use vegan sugars. No matter which way you make them, they’re sure to be delicious!
Table of Contents
What makes these blueberry oat bars gluten-free?
These blueberry bars use a gluten-free all purpose flour to make them gluten-free! I typically use Bob’s Red Mill 1-to-1 Gluten-Free Baking Flour (in the blue bag), but have also had success using King Arthur Gluten-Free All-Purpose Flour and Namaste Perfect Flour Blend.
Another important ingredient in these blueberry pie bars are the oats. You’ll need to use gluten-free certified oats or purity protocol oats.
Are oats gluten-free?
Oats are often cross-contaminated in the field with wheat, so ensure your oats are gluten-free certified (or even better yet, purity protocol) for this baked oatmeal to be gluten-free.
Purity protocol oats are best as they are the strictest form of testing to eliminate as much cross-contamination as possible. Purity protocol oats are typically grown in fields that have not grown gluten for a specified amount of years. Each manufacturer’s protocol is different – so be sure to check with suppliers and manufacturers to see what their rules and policies are.
Also, keep in mind that some people who have celiac disease are not able to tolerate oats even if they are certified gluten-free.
Here’s what you’ll need
Ingredients: gluten-free flour blend, gluten-free certified oats (or purity protocol oats), brown sugar, ground cinnamon, baking powder, salt,
- 8×8-inch baking dish
- Parchment paper (this makes removing the bars from the pan SO easy!)
How to make gluten-free vegan blueberry crumb bars
Step One: Make the crust
The crust comes together very quickly. Just combine gluten-free flour blend, gluten-free certified oats, brown sugar, cinnamon, salt, and baking powder. Whisk until combined. Then, pour in the melted dairy-free butter and vanilla extra and stir until it forms a dough.
Reserve 1/2 cup for the topping for later, and press the rest of the crust into the prepared baking dish until it’s as even as possible.
Step Two: Make the filling
Using fresh blueberries (or frozen if fresh are not in season), combine with granulated sugar, lemon zest, lemon juice, cornstarch and a pinch of salt.
The cornstarch is key here because it will help thicken our blueberry mixture.
Pour the blueberry mixture over the crust and spread it evenly over the crust.
Step Three: Sprinkle with topping
Remember that reserved crust? It becomes our topping! Just sprinkle the topping over the blueberry mixture.
It’s okay if there is some blueberry mixture poking through. In fact, that’s exactly what we want!
Step Four: Bake until golden
Put it all in the oven and bake at 375 F for 45-50 minutes. It will be ready when the blueberries are bursting and the crust is golden brown. The edges should be completely set and the middle should be just set.
Let the blueberry bars cool for an hour before proceeding with the glaze. You do not want to cut into warm blueberry bars because they will fall apart. This cooling time is KEY to this recipe’s success!
Step Five: Top with glaze.
Once the bars are cooled, combine the powdered sugar, lemon zest and lemon juice in a small bowl until completely smooth. If your glaze is too thin, you can add additional powdered sugar.
We want this to be a thicker glaze so that it doesn’t just run all over the bars and completely cover them. Instead, we’ll have some beautiful drizzles! Though, if you glaze is too thick to drizzle, you can add additional lemon juice or even some non-dairy milk or water to thin it out slightly.
With a spoon, drizzle the glaze over the bars. Don’t feel like you need to use all of the glaze, either. Use as much as you want. Then, let it set for 30 minutes before removing the bars form the baking dish and cutting into squares.
The parchment paper in the baking dish makes it easy to pull the bars out of the baking dish for easy slicing and cleaning!
Not all sugar is vegan. Some sugar is processed with bone char, making it not vegan. Check with your manufacturer to see how they process their sugar. When in doubt, purchase organic sugar which is not able to be processed with bone char.
Yes! If you do not need your blueberry bars to be dairy-free or vegan, you can use regular butter instead.
You sure can! If you do not need this recipe to be gluten-free, you can use regular all-purpose flour and regular old-fashioned oats in this recipe.
Yes and no. Oats do not contain gluten, but they are typically cross-contaminated with gluten in the growing, sorting, and packaging processed. Use gluten-free certified oats (preferably purity protocol oats) for this recipe if you need it to be gluten-free.
These gluten-free blueberry crumb bars so not necessarily need to be refrigerated. They’ll keep at room temperature in an airtight container for up to 3 days. However, if it’s summer or warm in your kitchen you may wish to keep them in your refrigerator instead. These bars also freeze beautifully!
You can use frozen blueberries if fresh blueberries are not available to you. Do not thaw your frozen blueberries before using! Keep in mind that frozen blueberries contain a lot of water, so you will need to bake your blueberry bars longer until the filling sets up, probably an additional 10-15 minutes total.
You don’t have to put glaze on top of these blueberry bars. It does give them that little something extra special, but the bars will still be delicious without the glaze!
More Gluten-Free Blueberry Recipes You’ll Love!
- Gluten-Free Blueberry Muffin Bread
- Blueberry Turkey Breakfast Sausage
- Easy Mini Blueberry Tarts – Gluten-Free and Vegan
- Gluten-Free Vegan Blueberry Banana Bread
- Gluten-Free Blueberry Scones
Gluten-Free Vegan Blueberry Crumb Bars
- 1 cups gluten-free flour blend
- 1 cup gluten-free certified oats
- 3/4 cup brown sugar (see notes for vegan option)
- 1 tsp cinnamon
- 1 tsp salt
- 1/2 tsp baking powder
- 1/2 cup dairy-free butter (melted)
- 1 tsp pure vanilla extract
- 2 cups blueberries
- 1/4 cup granulated sugar (see notes for vegan option)
- 1 tsp lemon zest (from 1 lemon)
- 1 tbsp lemon juice (from 1/2 lemon)
- 1 tbsp cornstarch
- pinch of salt
- 1/2 cup powdered sugar (see notes for vegan option)
- 1 tbsp lemon juice
- 1 tsp lemon zest
- In a large bowl, whisk together gluten-free flour blend, gluten-free certified oats, brown sugar, cinnamon, salt, and baking powder.
- Stir in melted dairy-free butter and vanilla extract.
- Reserve 1/2 cup of the crust for the topping. Press the remaining crust into a 8×8-inch baking dish lined with parchment paper. Make sure the parchment paper hangs over the edges of the pan so it's easy to remove the bars after baking.
- In a medium bowl, mix together blueberries, granulated sugar, lemon zest, lemon juice, cornstarch, and salt.
- Pour the blueberry filling evenly over the crust.
- Sprinkle the reserved topping over the blueberry filling.
- Bake at 375F for 45-50 min, until the blueberries begin to burst and the crust is a golden brown. Let sit for at least an hour, until cooled before adding glaze.
- In a small bowl, mix together the powdered sugar, lemon juice and lemon zest until smooth. If your glaze is too thick, you can add a tablespoon of non-dairy milk, water or additional lemon juice. If it is too thin, add more powdered sugar. Drizzle the glaze over the bars. Allow the glaze to set for 30 minutes.
- Using the parchment, remove the bars from the baking dish to a cutting board. Cut into squares to serve.
- Vegan Option – To make these blueberry crumb bars vegan, you’ll need to use vegan sugar. Some sugar is processed with bone char, which makes it not vegan. Be sure you know how your sugar is processed if you want these bars to be considered vegan. If you are in doubt organic sugar is not processed using bone char and is vegan.
- If you do not need these bars to be dairy-free or vegan, you can use regular butter in place of the plant-based butter.
- Not all oats are gluten-free, so use certified gluten-free oats or purity protocol oats. Keep in mind that some people who have celiac disease or gluten intolerances are unable to process oats as well.