The perfect summer breakfast or snack! These Blueberry Oatmeal Crumble Bars are made with real berries, naturally sweetened, and packed with flavor.
Being from Ontario, I look forward to blueberry season every year. It's the one time of year when blueberries don't cost an arm and a leg and you know every time you bite into a blueberry it's going to be perfect. Which is why I try to optimize the amount of blueberries I'm able to consume during the months of July to August. Like my Blueberry Protein Biscuits and my Greek Yogurt Blueberry Muffins, these Blueberry Crumble Bars are the perfect way to make the most of the season!
As a registered dietitian, I love a good quick, easy and nourishing meal. Which is why I love recipes like baked oats! They're the perfect way to minimize your time preparing and maximize your time eating a filling breakfast on a busy morning. Plus these blueberry oat crumble bars taste exactly like dessert, so who wouldn't want to wake up to these?
Why This Recipe Is Dietitian Approved
- Perfect for meal prep. These blueberry crumble bars are easy to make ahead and keep in the fridge or freezer for a quick grab-and-go option throughout the week.
- A great source of fiber. Oats, blueberries and chia seeds add fiber, making these a great option for a snack or even breakfast when paired with a source of protein.
- Minimal prep. These bars come together with simple ingredients and take less than 15 minutes of hands-on prep, making them an easy option for busy weeks.
Blueberry Oatmeal Crumble Bars Recipe
Ingredients, Swaps, & Tips
Oats: The base of these crumble bars! Rolled or quick oats both work well.
Eggs: Help bind the oat base together and add structure. For a vegan option, swap for two flax eggs (2 tablespoons ground flaxseed mixed with 6 tablespoons water).
Spices: Cinnamon, nutmeg and ginger add cozy flavor to these blueberry oat crumble bars. Cinnamon is the most important, so feel free to omit the others if needed.
Milk: Any milk works here! It helps create a moist, soft oat base. I personally use dairy milk for the added calcium, vitamin D and protein.
Maple syrup: These bars are naturally sweetened with maple syrup. Honey also works as a 1:1 substitute.
Coconut oil: Adds moisture and helps hold the bars together. Butter works well as a substitute.
Oat flour: Used in the crumble topping to help create the perfect texture. You can use store-bought oat flour or blend oats into a fine flour.
Blueberries: Fresh or frozen both work! If using frozen blueberries, don't thaw them first. You can also swap in any berries or a mixed berry blend.
Chia seeds: Help thicken the blueberry filling while adding extra fiber!
Walnuts: Add healthy fats and a delicious crunch to the crumble topping. Swap for another chopped nut, leave them out and add extra oats for a nut-free option.
The complete ingredient list with measurements can be found in the recipe card below.
Instructions
- Preheat oven to 350 ° F. Line an 8×8" pan with parchment paper. Set aside.
- In a medium bowl, whisk together eggs, milk, coconut oil, maple syrup and vanilla extract and mix well. Add oats, spices, baking powder and salt and stir until fully combined. Pour into an even layer along the bottom of your baking pan.
- Bake at 350℉ for about 20 minutes or until oats begin to turn golden brown in color.
- While the oats are baking, in a small saucepan over medium heat add blueberries and chia seeds (and optional lemon juice). Mash the berries using a fork so they release their juices. Once the berries warm the liquid will begin to mix with the chia seeds. Continue stirring until the chia jam has thickened. Remove from the heat and set aside.
- In a medium bowl add oats, oat flour, walnuts, cinnamon, coconut oil and maple syrup. Using a fork, mix everything together until a crumble forms. Place in the fridge to firm up.
- Once the oats are baked, Pour your blueberry jam in an even layer on top of the baked oats.
- Sprinkle the crumble topping over the blueberries. Bake for about 25 minutes or until top of oat crumble begins to brown and blueberries begin bubbling.
- Remove from the oven, let cool completely, and cut into squares.
Substitutions
Gluten Free
Oats are naturally gluten free, but they're often cross-contaminated during processing. Use certified gluten-free oats and gluten-free oat flour and the rest of the recipe stays exactly the same.
Vegan
Swap the 2 eggs for 2 flax eggs (2 tablespoons ground flaxseed mixed with 6 tablespoons water, left to sit for 5 minutes until gelled), and use a plant-based milk like oat or soy in place of dairy milk.
Dairy Free
If you use coconut oil instead of butter, the recipe is nearly dairy free! Just swap the 1 cup of dairy milk for your favorite plant-based milk (oat milk keeps the texture closest to the original).
Nut Free
Simply leave the walnuts out of the crumble topping and replace with an extra ½ cup of oats, or swap in sunflower seeds or pepitas for the same crunch.
Variations
- Switch up the berries: Swap the blueberries for any berries you love. I even like making a mixed berry version!
- Add chocolate: Add chocolate chips for a chocolate blueberry bar, or try white chocolate chips for a sweeter twist!
Equipment
Storage
Store these blueberry oat crumble bars in an airtight container in the fridge for up to 7 days. To reheat, warm them in the microwave for 20-30 seconds before serving.
To freeze, layer bars between sheets of parchment paper in an airtight, freezer-safe container for up to 2 months. Thaw overnight in the fridge or microwave straight from frozen.
Top Tips for Success
Let the bars cool completely before cutting. Allow them to cool in the pan for at least 30 minutes, or pop them in the fridge for 15 minutes to speed things up. The oat base needs time to fully set, otherwise you'll end up with a crumbly, saucy square instead of a clean bar. Use the parchment paper as a sling to lift the bars out of the pan before slicing for the neatest cuts.
Frequently Asked Questions
I recently updated this recipe so that we make the base for a little before adding the berries! This makes it easier to spread the jam on the baked oat base creating a less crumbly bar.
Yes! Honey works as a 1:1 swap for maple syrup in both the oat base and crumble topping. No other adjustments are needed.
Yes! Frozen blueberries work just as well as fresh. Just make sure not to thaw them before adding them to the recipe.
To boost the protein, add ½ cup of vanilla or plain protein powder to the oat base and adjust the oats to 1½ cups. You can also serve them with a side of Greek yogurt or eggs to make a more balanced breakfast.
More Meal Prep Recipes
If you liked blueberry oatmeal crumble bars, try one of these meal prep breakfasts:
- Healthy Coffee Cake
- Banana Oatmeal Chocolate Chip Muffins
- Apple Oatmeal Muffins
- Lemon Cheesecake Overnight Oats
See you in the kitchen!
PS. I love seeing my recipes in action! If you decide to make these blueberry oat bars, don't forget to snap a photo and tag me on Instagram- @nourishedbynic or leave a comment and rating below letting me know how you liked it!
📖 Recipe
Bluebery Oatmeal Crumble Bars
Ingredients
Oat base
- 2 medium eggs
- 1 cup milk
- 1 tablespoon coconut oil or butter melted
- ¼ cup maple syrup
- 1 teaspoon vanilla extract
- 2 cups quick, minute or rolled oats
- 2 teaspoon cinnamon
- ¼ tsp ground ginger
- ¼ teaspoon ground nutmeg
- 1 teaspoon baking powder
- ⅛ teaspoon salt
Berry layer
- 2 cups blueberries fresh or frozen
- 2 tablespoon chia seeds
- 1.5 tablespoon lemon juice optional
Crumble Topping
- ¾ cup oats
- ¼ cup oat flour
- ¼ cup walnuts chopped
- 2 tablespoon maple syrup
- 6 tablespoon coconut oil or butter melted
- ¼ teaspoon cinnamon
Instructions
- Preheat oven to 350 ° F. Line an 8×8" pan with parchment paper. Set aside.
Prepare the baked oat layer:
- In a medium bowl, whisk together eggs, milk, coconut oil, maple syrup and vanilla extract and mix well. Add oats, spices, baking powder and salt and stir until fully combined. Pour into an even layer along the bottom of your baking pan.
- Bake at 350℉ for about 20 minutes or until oats begin to turn golden brown in colour.
Make the blueberry chia jam:
- While the oats are baking, in a small saucepan over medium heat add blueberries and chia seeds (and optional lemon juice). Mash the berries using a fork so they release their juices. Once the berries warm the liquid will begin to mix with the chia seeds. Continue stirring until the chia jam has thickened. Remove from the heat and set aside.
Prepare your crumble topping:
- In a medium bowl add oats, oat flour, walnuts, cinnamon, coconut oil and maple syrup. Using a fork, mix everything together until a crumble forms. Place in the fridge to firm up.
Assemble:
- Once the oats are baked, Pour your blueberry jam in an even layer on top of the baked oats.
- Sprinkle the crumble topping over the blueberries. Bake for about 25 minutes or until top of oat crumble begins to brown and blueberries begin bubbling.
- Remove from the oven, let cool completely, and cut into squares.
Chane Hawksley says
These are so good! Love all your recipes, but these almost taste more like dessert than breakfast 😅
Millie says
I used monk fruit instead of maple syrup and it turned out great. Thanks so much for an awesome recipe!
Sandy says
Can I use almond milk for this blueberry crumble? My daughter in law is gluten and dairy free.
Nicole Addison says
Hi Sandy,
Yes! Any type of milk or milk alternative will work just fine!
Nicole
Jane says
They turned out great. I used mixed berries n also topped them w/ vanilla Greek yogurt! Thx for sharing the recipe!
Nicole Addison says
The vanilla Greek yogurt sounds like such a great addition! So glad you enjoyed!!
Tina says
Delicious! Thank you!
Nicole Addison says
Hi Tina! I'm so glad you enjoyed this recipe!
the_crustmaker says
lovely recipe thank you! i prebaked the oatmeal layer while prepping the fruit and topping since i dislike a soggy bottom but i'm sure it would've been fine either way. delicious with blueberry, apple, plums and pear filling :))