This post may contain affiliate links. Read our disclosure policy.

These blueberry oatmeal bars are made with a thick layer of oatmeal crust, a sweet bubbly layer of fresh blueberries, and topped with more cinnamon crumble. They’re simple to make, easy to freeze, and delicious any time of day.

Need another healthy breakfast or snack option with fresh blueberries? Try these blueberry muffin energy bites or naturally sweet blueberry popsicles.

gooey blueberry filling coming out of the sides of oatmeal crumb bars
Save this Recipe!
Enter your email & I’ll send it straight to your inbox.
Please enable JavaScript in your browser to complete this form.

I had some blueberries remaining from a 5-pound box and I wanted to use ingredients I had on hand — the final product was these gooey blueberry oatmeal bars. 

Blueberry Oatmeal Bars

Imagine your favorite buttery crumb topping on coffee cake muffins. Take all of of that sweet goodness and press it into the bottom of a pan, top it with gooey blueberry filling, and more crumb topping sprinkled on top.

That’s exactly what’s happening in these blueberry oatmeal bars!

There are three layers, but you only need to make 2 of them because the top and bottom layers are from the same dough. This simple dessert makes such a statement!

I highly recommend serving them warm with a scoop of vanilla ice cream for the perfect dessert. I love warm fruit desserts with ice cream (helloooo peach apple crisp).

Next time you have extra blueberries or are just craving a sweet to go with your cup of coffee, I hope you think of these blueberry oat bars (but you wouldn’t be mad if you made a blueberry muffin either).

Looking for a breakfast version? Try this blueberry baked oatmeal next!

a bite taken out of a blueberry crumb bar on the counter

The Simple Ingredients

Here are the simple ingredients for these easy blueberry oatmeal bars. Most are pantry staples and easy (and affordable) to find in the grocery store. Jump down to the recipe card for exact measurements.

  • Unsalted butter: I love the flavor butter gives this recipe. We tested these with vegan butter and it worked well, but you could also use coconut oil.
  • Flour: White whole wheat flour is a great option for whole grains. We also tested this using 1:1 gluten-free flour (Bob’s Red Mill). 3/4 cup 
  • Old fashioned oats: This is the best type of oat for this recipe, but instant oats or quick oats will work if you have those on hand.
  • Cinnamon, vanilla extract, and salt: For extra flavor.
  • Brown sugar: I like to use the brown sugar if I’m making it for dessert, but I opt for coconut sugar or maple syrup for the breakfast version.
  • Blueberries: Fresh or frozen work well (so you can have these year round!)
  • Pure maple syrup: This helps sweeten up the blueberries just enough.
  • Lemon juice: The acid balances the sweetness in this recipe. Add a little lemon zest too if you feel like it!
  • Corn starch: This helps the blueberry layer become extra gooey. Great subs for this are tapioca or arrowroot starch.
oatmeal crumb bars cut into squares on a countertop

How to Make Blueberry Oatmeal Bars

Here are the basic steps, with images, for these blueberry oatmeal breakfast bars. Skip down to the recipe card below for the full instructions and a printable recipe.

Mix the oatmeal crumb Add all of the dry ingredients to a large bowl with the melted butter and mix well until it starts to come together and creates large, sandy clumps.

oatmeal crumb dough in a bowl with a rubber spatula

Press it into a square pan. Reserve 1 heaping cup of the mixture then firmly press the rest into the bottom of a square pan lined with parchment paper.

oatmeal brown sugar crumb pressed into a square pan

Make the blueberry filling: Mix all of the blueberry filling ingredients together (you can use the same bowl).

blueberries tossed in sugar and cornstarch

Assemble: Pour the blueberries evenly on top of the bottom layer. Sprinkle the reserved crumble on top.

fresh blueberry filling on top of oatmeal crumb dough

Bake: Bake for 50-55 minutes, or until the top turns golden brown and the blueberries are bubbling.

Success tip: check the bars with 15 minutes left and cover the pan with foil if the top is browning too much.

crumb topping on top of blueberry filling before baking

Variations and Dietary Modifications

  • Use other fresh fruit: If you’re not a big fan of blueberry flavor or you have peaches or strawberries on hand, they would be great options!
  • Gluten-free: Use 1:1 gluten-free flour and gluten-free rolled oats.
  • Dairy-free: Swap the butter or vegan butter or coconut oil.
  • Refined sugar-free: Use coconut sugar and maple syrup instead of brown sugar and granulated sugar.
  • Add protein: Serve with a scoop of Greek yogurt or drizzle natural peanut butter on top.

Storage Instructions

These can easily be a meal prep recipe! Kids love these in the morning, so follow the instructions to individually wrap each oatmeal crumble bar separately if you want to freeze them so they last longer.

Storage: Allow the bars to cool to room temperature and store any leftovers in an airtight container in the fridge for up to 5 days.

Freezer: Cut the bars into squares then wrap each one in plastic wrap. Place them in a freezer bag or airtight container and freeze for up to 3 months. Thaw overnight then warm in the microwave until warmed through.

two blueberry oatmeal bars stacked on a countertop

If you make these delicious blueberry oatmeal bars, I’d love for you to give it a star rating ★ below. You can also tag me on Instagram so I can see it!

More Blueberry Recipes

Looking for more delicious recipes with blueberries? Give these recipes a try next time:

Tap stars to rate!
5 from 2 votes

Blueberry Oatmeal Bars

Prep: 15 minutes
Cook: 55 minutes
Total: 1 hour 10 minutes
These blueberry breakfast bars are made with a thick layer of oatmeal crust, a sweet bubbly layer of fresh blueberries and topped with more cinnamon crumble. They're simple to make, easy to freeze and delicious any time of day.

Save this Recipe!

Enter your email and we’ll send it directly to you.
Please enable JavaScript in your browser to complete this form.
Servings: 16 bars

Ingredients

Crust and Crumble Topping

  • 1 cup (2 sticks; 227g) unsalted butter melted
  • 2 cups (250g) all-purpose flour gluten-free if needed
  • 1 1/2 cups (150g) old-fashioned rolled oats (gluten-free if needed)
  • 1 teaspoons cinnamon
  • 1/2 teaspoon salt
  • 1 cup (200g) light brown sugar packed

Blueberry Layer

  • 16 ounces fresh blueberries (Note 2 Frozen)
  • 1/4 cup granulated sugar
  • 2 Tablespoons fresh lemon juice (juice from 1/2 lemon)
  • 1 Tablespoon cornstarch

Instructions 

  • Preheat the oven to 350°F and line an 8×8-inch metal pan with parchment paper.
  • In a large bowl, stir together the melted butter, flour, oats, sugar and salt. The mixture will be dry and sandy with some larger, well-formed crumble pieces. This makes up the crust and crumble. Set 1 heaping cup (I used almost 1 1/2 cups) of the mixture aside for the crumb topping.
  • Transfer the remaining crumb mixture to the prepared pan, and use a spatula or your fingers to press the mixture evenly into the bottom of the pan to create an even crust,
  • In the same or a separate large mixing bowl, add all ingredients for the blueberry layer and toss to coat the berries in the sugar and cornstarch. Dump the blueberries over the bottom layer.
  • Sprinkle the reserved crumb topping over the blueberries. There will be blueberries still showing, this is what you want.
  • Bake in the preheated oven for 50-55 minutes, or until the crumble is golden and the blueberrries are bubbling around the edges. Check the bars with 15 minutes remaining and cover with foil if the top is starting to look to brown.
  • Allow the bars to cool for 30-60 minutes then use the parchment paper overhang to remove the bars and cool them completely. You can place them in the freezer to speed up the cooling process. Slice cooled bars into squares and enjoy.
Last step! If you make this, please leave a review letting us know how it was!

Notes

Note 1. Frozen Blueberries. I don’t recommend using frozen blueberries because the filling will be more soupy. If you choose to use frozen blueberries, do not thaw. The bars will take longer to cook due to the increased liquid. 
Gluten-free: use 1:1 gluten-free flour and gluten-free rolled oats.
Dairy free: swap the butter or vegan butter or coconut oil.
Refined sugar free: use coconut sugar instead of brown sugar and maple syrup instead of granulated sugar. 

Video

Equipment

  • 8×8 inch baking pan

Nutrition

Serving: 1bar | Calories: 271kcal | Carbohydrates: 38.1g | Protein: 3.1g | Fat: 11.8g | Cholesterol: 30.5mg | Sodium: 78.4mg | Fiber: 2.1g | Sugar: 18.2g | Vitamin A: 97.9IU | Vitamin C: 3.5mg

Nutrition information is automatically calculated, so should only be used as an approximation.

Leave a comment

Your email address will not be published. Required fields are marked *

Recipe Rating




6 Comments

  1. Maureen says:

    5 stars
    I made these for Easter and everyone asked for the recipe! The perfect mix of gooey and crunchy. Sweet and satisfying!

    1. Molly Thompson says:

      Thank you so much!

  2. Sue says:

    These look SO yummy…I sure would like to try this recipe but I don’t like blueberries – would other fruits work? raspberries? cherries?

    1. Molly Thompson says:

      Hi Sue! Yes, you could use any other berry for this recipe. Thanks!

  3. Kristen says:

    5 stars
    These bars are great! I’m surprised there aren’t any reviews for this recipe yet. I was looking for something to use up extra blueberries and this was perfect. I did need to add 1/4 cup or so of frozen berries to get to 16oz and swapped the granulated sugar for maple syrup but they were perfect even with the changes. I also loved that the crust was used for the bottom and top. I ate them as dessert and breakfast lol. My husband loved these and requested I make them again so I will be soon. Thanks, Molly!

    1. Molly Thompson says:

      Thank you, Kristen! I’m so glad you took the time to comment. Thank you for sharing that maple syrup works too. I’m going to try it that way too!