Blueberry Oatmeal Bars

Published: Apr 11, 2025 · Modified: Apr 10, 2025 by Colleen 22 Comments

These delicious blueberry oatmeal bars are bursting with juicy blueberries, sandwiched between a buttery, crunchy oatmeal crumble bar base and topping. Inspired by classic blueberry pie bars, this recipe features bold blueberry flavor in every bite with a handful of basic ingredients. It's an easy recipe that's guaranteed to be a huge hit with family and friends! Enjoy these amazing blueberry bars for breakfast, dessert, or as a midday pick-me-up.

A freshly baked batch of blueberry oatmeal bars on parchment paper.

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If you love blueberries, you will also love these blueberry almond flour muffins, or my gluten-free blueberry scones. You might even love a blueberry martini!

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Why you're going to love blueberry oat bars
Ingredients
How to make it, step by step
Helpful Tips
Serving suggestions
FAQs
More recipes with oats
Recipe
Comments

Why you're going to love blueberry oat bars

Simple Ingredients: Whether you've just returned from blueberry picking or are using packaged berries from the grocery store, these easy blueberry oatmeal bars come together quickly with basic pantry staples that you already have on hand.
Easy to Customize: You can easily adapt this recipe to be gluten-free, dairy-free, or vegan. Check out the tips section for tasty add-in ideas, too!
Serve Whenever: Enjoy them as blueberry breakfast bars first thing in the morning or after a hearty meal with a scoop of vanilla ice cream. They are also a perfect snack option with a cup of coffee or tea.

Ingredients

Ingredient quantities and detailed instructions are in the printable recipe card at the bottom of this post.

All-purpose flour: White whole wheat flour is another option, which has more nutrition than all-purpose flour. If you stick to gluten-free recipes like I do, use oat flour or a 1:1 gluten-free flour blend.
Quick-cooking oats: I prefer to use quick oats because they're softer and cook faster than old-fashioned rolled oats. Quick-cooking oats are not the same as instant oats and should not be used interchangeably.
Brown sugar: I use light brown sugar in the base of the bars. Dark brown sugar would add a bolder caramel flavor, and coconut sugar would give the bars a slight tropical flair.
Salt: The salt balances out the natural sweetness of the sugars and berries. Kosher salt or coarse sea salt is best.
Butter: Use unsalted butter, as the recipe already contains salt. If you only have salted butter, that's ok, just omit the added salt. To make this recipe dairy-free, swap the butter for vegan butter or coconut oil.
Fresh blueberries: Frozen blueberries also work just fine here, and there's no need to thaw them first! Two cups of blueberries are roughly equivalent to 10 ounces by weight.
Sugar: I use granulated sugar, since it dissolves easily into the blueberry filling as it bakes. You can use brown sugar instead, but the molasses content will add more moisture to the filling.
Lemon juice: For an extra dose of tartness, you can add more fresh lemon juice and even some lemon zest.
Cornstarch: Cornstarch helps thicken the juices, resulting in a texture similar to that of blueberry pie filling.

The ingredients for making this recipe in glass bowls.

How to make it, step by step

Combine the oats, flour, brown sugar, salt, and melted butter in a large bowl.
The mixture will be crumbly.

Steps one and two of the recipe process.

Press half of the oat mixture into the bottom of the prepared pan.
Combine the blueberries, lemon juice, white sugar, and cornstarch in a separate bowl.

Steps three and four of the recipe process.

Spread the blueberry mixture evenly over the crust.
Sprinkle the remaining crumble mixture over the blueberries.

The final two steps of the recipe process before baking.

Bake until the blueberry filling is set and the topping is golden brown. Cool on a wire rack before cutting into squares.

The pan of baked blueberry oatmeal bars cooling on a wire rack.

Helpful Tips

Use quick-cooking oats. Quick oats are ideal for blueberry oatmeal bars because they blend more smoothly into the dough, resulting in soft, slightly chewy bars with a firm enough texture that isn't too dense.
Make it vegan and dairy-free. Just swap the regular butter with vegan butter or coconut oil.
Add nuts, seeds, or nut or seed butter. Want to add some healthy fats and plant-based proteins to your blueberry oatmeal breakfast bars? Mix in half a cup of chopped walnuts, almonds, or pecans with the oatmeal crumble topping. You could even stir in a couple of tablespoons of peanut butter, almond butter, or sunflower seed butter.
Add extracts or spices. Add a teaspoon of vanilla extract or ½ teaspoon of almond extract to the blueberry mixture for an extra flavor boost. Warm spices, such as cinnamon and nutmeg, would add more depth.
Let the mixture cool to room temperature before slicing. If you slice them too soon, you'll end up with a soft blueberry crumble that falls apart, not blueberry oat bars. Still delicious, but not the right texture for this recipe.
Storage. Store leftover bars in an airtight container for up to a week. Keep them in the refrigerator, since the buttery crumble base will soften at room temperature.
Freezer-friendly. The cooled bars can be stored in the freezer for up to 3 months. I recommend wrapping each bar individually with plastic wrap and storing them together in a freezer bag or an airtight container. Thaw frozen bars in the fridge overnight before serving.

Blueberry oatmeal bars on a white counter top.

Serving suggestions

Blueberry oatmeal bars are great for breakfast! Serve them with Greek yogurt and fresh fruit, like sliced banana, strawberries, or extra blueberries, or chocolate chia pudding. These amazing crumble bars also pair well with hot or iced coffee, fruity herbal tea, or a simple glass of milk or unsweetened almond milk.

Serve blueberry oat bars for dessert with a scoop of ice cream or frozen yogurt and a dollop of whipped cream on top.

FAQs

Can I use frozen blueberries?

Sure! There's no need to thaw and drain frozen blueberries for this recipe. Mix them with the remaining filling ingredients and layer them over the crust, just as you would fresh berries.

Can I use whole oats or instant oats instead of quick-cooking oats?

These different types of oats are not interchangeable. Whole oats, also known as old-fashioned oats, are thicker and denser than quick-cooking oats. You can use them in this recipe, but please note that the cooking time may be longer. On the other hand, instant oats are pre-cooked and even thinner than quick oats, so they tend to become mushy in baked goods.

How do I make this recipe gluten-free?

It's easy! Use gluten-free certified quick oats and oat flour or a 1:1 gluten-free flour blend in place of all-purpose flour.

More recipes with oats

I love to cook and bake with oats, they're nutritious and versatile! Some of my other favorites for breakfast are chocolate baked oats, banana blueberry oatmeal muffins, or cranberry oatmeal muffins. And of course overnight oats are a great way to start the day. Maple walnut overnight oats are amazing.

But oats can be more than breakfast! Try a delicious oat-y dessert like apple and blackberry crumble, rhubarb crisp, or air fryer apple crisp.

For snacking, there are always classic oatmeal raisin cookies, and oatmeal energy bites are delicious, too.

Did you make this recipe? Please leave a rating in the comments below and let us know how it turned out. Did you make any changes? We would love for you to share and your feedback is important! Thank you for visiting The Food Blog!

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