Blueberry Overnight Oats are a deep, dark and beautiful way to start your morning. Make the blueberry sauce from scratch, then turn to the overnight oat mixture to soak in the fridge. A healthy and delicious meal prep breakfast for busy mornings!

And if you’re looking for more blueberry recipes, check out blueberry crumb bars, blueberry oatmeal muffins, blueberry banana smoothie, blueberry muffin bread and blueberry scones.

jars of blueberry overnight oats next to blueberry sauce

This post is sponsored by California Giant Berry Farms. I am so excited to continue our partnership together and share more berry-focused recipes with you! Thank you for supporting the brands that help Fit Mitten Kitchen bring you new and exciting recipes!

How to Select the Best Blueberries

Peak blueberry season in the United States is during the summer months, between early June – early August, depending on where you live. Thankfully, California Giant has amazing national and international growers to provide us with the best berries year round. They also share some great information on blueberries in regards to selecting, storing, washing, freezing and more.

When shopping for blueberries at the grocery store, seek out berries that are:

Deep blue in color with a light, silvery powder (called bloom)
Naturally plump with smooth skin
Firm and dry, with no signs of fuzz, mold or mushy berries

Be sure to check out my farm tour with California Giant growers, here!

Ingredients You Will Need

The ingredients for this blueberry overnight oatmeal recipe are broken down into three parts – blueberry sauce, overnight oats and toppings. Most are simple pantry ingredients you can find in my healthy pantry staples.

Blueberry Sauce

fresh blueberries – you will need 1 cup blueberries, or approx half a pint. If you have a stash of frozen California Giant blueberries from a good sale at the store, you can use those too!
lemon juice – adds a natural acidity and enhances the sweetness of the berries.
maple syrup – for a touch of smoky sweetness. Feel free to omit if your berries are super fresh and sweet and already have delicious flavor.

Overnight Oats

Greek or Skyr Yogurt – either Greek or Skyr yogurt will do, just make sure it is a plain yogurt. Both provide a thick consistency and high protein content to keep you full and focused.
non-dairy milk – any dairy-free milk will work, such as almond milk, cashew milk, soy milk, oat milk or full-fat coconut milk. You can also use regular dairy milk, if not a dietary concern.
maple syrup – for subtle sweetness, feel free to omit or add at the end.
vanilla extract – for a sweet, vanilla flavor.
rolled oats or quick oats – I used quick or instant oats, which allowed the oats to soak to the right pudding-like texture in just 2 hours. Regular oats (old-fashioned rolled oats) are your next best option, but they will take a bit longer to soften.
chia seeds – for healthy fats, a great source of fiber and subtle crunch. The chia seeds also gel-up slightly, creating a thicker texture.
ground cinnamon – for a subtle warming flavor.

PRO TIP: For a dairy-free and vegan option, stick to plant-based versions of yogurt and milk. You can even replace the yogurt entirely with dairy-free milk, if that’s more your style.

overnight oats ingredients in bowls and on plates with text labels over ingredients

Toppings

The toppings here are totally optional but I love to add a little extra goodness! Here are some of my favorites:

blueberries – more fresh fruit never hurt and they add pops of sweet, sweet berry flavor.
hemp hearts – for an extra protein boost and heart healthy fats.
favorite nut butter – use whatever you have on hand – almond butter, peanut butter or cashew butter.
granola – my maple walnut granola is delicious here – adds a lovely crunch factor!

Blueberry Sauce

I am a huge fan of blueberries, and for good reason. They are gorgeous, sweet, juicy little things that break down into a jammy, almost too-pretty-to-eat blueberry sauce. Here’s how to do it:

Combine Blueberries and Lemon Juice

In small saucepan set over medium heat, add blueberries, lemon juice and maple syrup, if using the extra sweetener. Cook until the juices begin to release, for about 8 minutes. Then as you see the juices releasing, begin mashing the whole berries with the back of a wooden spoon.

Simmer and Thicken

Next, continue simmering for an additional 2-3 minutes, until the sauce is glossy and slightly thickened. Remove the pan from the heat to cool and the sauce thickens slightly upon standing.

California Giant blueberries clamshells next to blueberries in small pan

Overnight Oats

Now, we move on to the step-by-step process for overnight oats. All it takes is one bowl and about 5 minutes to combine everything!

Combine Wet Ingredients

Add yogurt, milk, maple syrup, and vanilla extract to a medium bowl. Whisk until everything is well combined.

overhead view of thickened overnight oats in glass bowl next to light blue spatula

wooden spoon in pan of healthy blueberry sauce for blueberry overnight oats

Add Dry Ingredients

Next, stir in the oats, chia seeds and pinch of ground cinnamon.

Refrigerate

Cover and store the oats in the fridge for at least 2 hours, or overnight. You can portion into individual servings or store covered in a larger bowl.

Enjoy!

In the morning and when ready to enjoy, taste test for consistency. If you’d like it thinner, stir in a couple splashes of milk. Enjoy cold or warm through in the microwave, then top with your favorite toppings.

Ways to Serve

You can combine the cooled blueberry sauce with the overnight oats BEFORE putting in the fridge, OR after – the choice is yours. Either way works.

Pairfait Style: Spoon 1-2 tablespoons of the blueberry sauce into the bottom of your jar or serving dish, then top with the oats and more blueberry sauce. Reserve the toppings until the moment you are going to serve.
Cooled + Stored Separately: Store the blueberry sauce and overnight oats in two separate airtight containers in the fridge. Assemble as you wish when ready to enjoy.

overhead view of blueberry sauce swirled into blueberry overnight oats next to California Giant blueberries clamshell and blueberry sauce

How Long Do Overnight Oats Last?

Overnight oats are a meal prep staple in my home and they will last up to 5 days in the fridge, stored in an airtight container or wide-mouth mason jar.

The oats will soften and thicken as they sit, so you will want to give it a good stir before scooping and enjoying. Depending on your consistency preference, adding a splash of milk on days 4-5 will loosen the thicker oatmeal to the right texture.

straight on view of blueberry overnight oats jar layered with blueberry sauce, next to spoon with milk glass in background

Recipe Tips & Notes:

The type of oats will determine soak time. Quick oats take approx 2 hours, rolled oats will take anywhere from 4-6 hours and overnight steel cut oats will take at least 8-10 hours.
The texture of the oats should be a pudding-like consistency. You want them to be soft, tender and scoop-able. Again, consistency is kind of personal preference, so add a little extra liquid if you prefer!

More Overnight Oats Recipes:

If you make this Blueberry Overnight Oats recipe, be sure to leave a comment and review on the blog! I love hearing from you, and it helps others learn more about the recipe too! Xx Ashley

The Best Blueberry Overnight Oats

How to Select the Best Blueberries