Name: Sourdough Blueberry Cookies
Prep time: 10 min
Cook time: 15 min
Total time: 1465 min
Ingredients: 100 g Butter ((melted - I used salted butter)); 100 g Brown Sugar; 1 Egg; 5 g Vanilla Extract; 100 g Sourdough Starter; 170 g All Purpose Flour; 50 g Oats; 5 g Baking Soda; 3 g Salt; 90 g Dried Blueberries; 1 Lemon ((zest and 15g juice only)); 100 g Cream Cheese ((softened at room temperature)); 40 g Butter ((softened at room temperature)); 240 g Powdered Sugar; 15 g Lemon Juice

With crispy edges and a soft centre, these sweet blueberry sourdough cookies utilise 100g of sourdough starter to ferment the cookie dough for a minimum of 2 hours and up to 24 hours. You'll get all the blueberry goodness you need, along with using up some of your sourdough starter! They make a gorgeously sweet afternoon snack!

Sourdough blueberry cookies baked and topped with a lemon cream cheese frosting.

Sourdough cookie recipes are such a great way to use your sourdough starter for recipes other than sourdough bread.

If you love using blueberries when you bake, then make sure you check out these overnight sourdough blueberry muffins, blueberry sourdough sheet pan pancakes, sourdough blueberry cheesecake brioche rolls and sourdough lemon and blueberry bread.

Sourdough blueberry cookies topped with lemon cream cheese frosting sitting on a wire cooling rack. To the left of the cookies you can see a blue and red striped dish towel and a jar of lemon cream cheese frosting with a wooden handled offset spatula.

Why You'll Love This Recipe!

Fermented Flour - These delightful sourdough blueberry cookies are fermented for a minimum of 2 hours and up to 24 hours, meaning that all of the flour in this recipe is fermented with your sourdough starter.

Crispy Edges, Chewy Centres - Just like these soft and chewy sourdough chocolate chip cookies, these sourdough blueberry cookies have crispy edges and chewy centres ... which kind of makes them the perfect sourdough cookie, right? They are definitely not a cakey cookie!

Lemon Cream Cheese Frosting - The lemon cream cheese frosting takes these sourdough cookies to the next level! It's definitely optional, but highly recommended! The cookies themselves contain some lemon zest which pairs really nicely with the lemon frosting. They kind of taste like blueberry cheesecake sourdough cookies!

An assortment of sourdough blueberry cookies sitting on a black wire cooling rack. Some of the cookies have lemon cream cheese frosting spread on top.

Active Sourdough Starter or Sourdough Discard?

One of the best things about this recipe (and in fact many sourdough discard recipes) is that you can use either active sourdough starter or sourdough discard with no changes to the recipe.

These cookies are fermented and use baking soda as leavening, so using either sleepy discard or bubbly active starter won't make too much difference.

The main difference you will find in using discard with these cookies is the flavor. Try not to use old, sour discard for these cookies as it can really taint the flavor of the sourdough cookies once they are baked.

You can read about the differences between sourdough starter discard and active sourdough starter here.

Jar of active sourdough starter sitting on a checked fabric napkin. You can see a digital scale in the background of the photo.

How To Make Sourdough Blueberry Cookies

These sourdough discard blueberry cookies remind me of the flavor of a delicious sourdough blueberry muffin, they're almost like sourdough blueberry muffin cookies! I've used dried blueberries that I've soaked in a little lemon juice to plump them up. You can use fresh blueberries if you'd like to.

I avoid using frozen blueberries, particularly as this recipe is fermented. They tend to bleed once they defrost and can make the sourdough blueberry cookie dough too soft. The addition of the lemon zest and lemon juice makes these lemon blueberry cookies pop! It really enhances the blueberry flavor!

I like to leave all my ingredients out at room temperature for a bit before making this recipe. Having everything at the same temperature really helps the ingredients to meld together more easily.

Flat lay of ingredients necessary to make sourdough blueberry cookies with cream cheese frosting.

Before You Start

Before you start making the cookie dough, add the dried blueberries, lemon zest and lemon juice to a small bowl. Stir to combine and leave to sit while you get the other ingredients organised.

Now Let's Get Mixing!

To a medium sized mixing bowl, add the melted butter, brown sugar, egg and vanilla extract. Whisk until lighter in color and texture.

Now, add the sourdough starter to the mixture and whisk again to combine. You're looking for the wet ingredients to form a light and fluffy mixture.

To the top of this mixture, add the dry ingredients - all purpose flour, rolled oats, baking soda, salt and the dried blueberry and lemon mixture. You might see the baking soda fizz as the lemon juice hits it.

Mix everything together with a spatula until well combined. Cover with a plastic cover and place into the fridge for around 2 hours. You can leave the mixture to ferment for up to 24 hours if you like.

How To Bake Sourdough Blueberry Cookies

When you're ready to bake the cookies, preheat the oven to 170C (340F). Line two cookie sheets with parchment paper and grab a cookie scoop.

Scoop out portions of dough that weigh around 40g (I made 16 cookie dough balls weighing 40g each). Put each ball of dough onto the cookie sheet and push down a little with your fingers to flatten.

Place the trays of sourdough blueberry cookies into the oven and bake for 15 minutes or until the edges are golden brown but the middles are still soft.

Remove them from the oven and allow to cool on the tray for 10 minutes before transferring to a wire rack to fully cool.

How To Make Lemon Cream Cheese Frosting

To make the frosting, add the cream cheese, butter, powdered sugar and lemon juice to the bowl of a stand mixer and whisk together until light and creamy.

Once the cookies have cooled completely, spread liberally with icing and allow a few hours for the icing to "set" before serving.

Flavor Variations To Try

While these sourdough blueberry cookies are perfect just as they are, there are a few things you could do to change them up a little, depending on the occasion!

Add 200g of white chocolate chips to the cookies (lemon and white chocolate actually go really well together). I like to just use a simple lemon glaze on these rather than the lemon cream cheese frosting if I'm using white chocolate chips.
Swap the lemon zest and lemon juice for orange zest and orange juice for a different citrus twist.
Swap the vanilla extract for almond extract when baking these sourdough cookies.

How To Store + Freeze

These sourdough blueberry cookies will last around a week stored in an airtight container. I find I get better results storing them in a glass jar, rather than plastic - as that tends to make them lose their crispy edges.

I advise you to only frost the cookies when you are going to be eating them. If you store the cookies with the glaze, they will go soft and quite cake like (still delicious, but a definite change in texture).

The cookie dough freezes really well - form into balls and snap freeze on a baking tray before transferring to a sealed ziploc bag. You can bake the cookies from frozen when you want to. And the best thing is, you can just bake a few at a time if you want to, rather than baking a whole batch.