Light and Fluffy Sourdough Peanut Butter Cookies

My sourdough peanut butter cookies are my husband’s favorite! They’re light and fluffy and easy enough to make any day of the week. The additional egg yolk and using a fork to mix, gives them the perfect texture. It always makes me so happy when I whip up a batch of these cookies and I see Tyler’s smile! I hope these cookies make someone in your life smile like they have in mine!

This post may contain affiliate links of items I know and love. Read our disclosure policy for more information. I NEVER use AI (artificial intelligence) to create content for Plum Branch Home. Recipes, blog posts, photos, videos, podcasts, social media content: everything is made from scratch by me, Molly LaFontaine. After developing my recipes, they’re tested 2x by my husband, Tyler, and I before publishing. What you see from Plum Branch Home is real. It’s made for a reason, tested, and loved!

If you want to make this recipe but don’t have a sourdough starter, no worries! Grab my free guide so you can make your own starter at home.

If you’re new to sourdough baking and feel hesitant, or you have questions, I’ve got something for you! I broke down the basics of what you need to know about sourdough baking in my free sourdough baking guide for beginners. I highly recommend grabbing a copy!

Inspiration Behind My Sourdough Peanut Butter Cookies Recipe

My husband LOVES peanut butter cookies; they’re his favorite! So, I wanted to make a sourdough version from-scratch that would be easy to whip up for him any day of the week.

I decided to use a fork instead of an electric mixer and an extra egg yolk to create a light and fluffy texture. When he tried the first batch he said, “These are the best peanut butter cookies I’ve ever had!”. After that, I knew I had to get them on the blog to share with you.

Why We Love These Cookies and Think You Will Too

• Easiest Sourdough Peanut Butter Cookies! All you need is a fork  — no electric mixer or fancy equipment for these cookies.
• Beginner-Friendly: The steps are simple to follow; no overwhelm here.
• Wholesome Ingredients: Each ingredient is wholesome, so you can feel good about making these cookies for your loved ones.
• Perfect for Freezing: You can easily freeze this dough or baked cookies.
• Delicious Holiday Treat: If you’re looking for a great holiday cookie recipe, look no further.
• Better Than Store-Bought: These cookies will replace store-bought peanut butter cookies; they’re just that good!
• Light and Fluffy Texture: The extra egg yolk creates the perfect texture!
• Only One Sugar: These cookies don’t have excess sugar, just a little brown sugar for the perfect sweetness.

Best Peanut Butter to Use

Natural, unsweetened, creamy peanut butter is the best to use! By using this kind, you get to adjust how much sugar and salt go into your cookies plus you’re keeping additives out.

I like to use Costco’s Kirkland natural peanut butter or the Teddie All Natural brand at Walmart, but you can use any brand you desire. Different brands of peanut butter will create a different peanut butter flavor.

Why Make Peanut Butter Cookies with Sourdough Discard

When you make peanut butter cookies with sourdough discard, you get fermentation benefits from the sourdough starter’s cultures. If you cold ferment the dough in the fridge for 12-24 hours before baking, those cultures ferment the other ingredients. This cold fermentation is optional but adds even more fermentation benefits!

My Tips for Making the Best Peanut Butter Sourdough Cookies

• Read the full recipe before getting started so you know what to expect.
• Use a fork, not a mixer, to keep these cookies light and fluffy!
• Don’t leave that second egg yolk out. It really makes a difference!
• Remember the dough will be sticky; that’s what we’re looking for. The peanut butter oil will help it not stick to your hands.
• After scooping, roll the dough into a ball. It helps the cookie keep a circular shape.

Ingredients You’ll Need (with notes and substitutions)

Note: Please see the recipe card at the bottom of this blog post for measurements

• light brown cane sugar: I like to use cane brown sugar; Florida Crystals is my favorite wholesome brand
• melted butter: I use salted but you can use unsalted, if desired
• egg: a large egg works great
• egg yolk: adding only the 2nd yolk and leaving out the 2nd white gives the cookies that fluffy texture
• milk: I like to use whole milk but you can use any
• pure vanilla extract: I don’t recommend using imitation flavoring
• natural unsweetened creamy peanut butter: I like to use anything from Costco’s Kirkland brand to the Teddie All Natural brand at Walmart
• sourdough discard: this is just unfed sourdough starter
• sea salt: I like using sea salt for a wholesome option
• baking soda: you can use any brand you have on hand
• baking powder: I like to use an aluminum-free version to keep these cookies wholesome
• all-purpose flour: I use organic, unbleached but you can use any

Helpful Kitchen Tools for this Recipe

This section contains Amazon affiliate links to items I use and love for this recipe.

• large baking sheet
• mixing bowl
• unbleached parchment paper

How to Make Sourdough Peanut Butter Cookies

Note: Please see the recipe card at the bottom of this blog post for the full written recipe.

Preheat oven to 350 degrees Fahrenheit and line 2 baking sheets with parchment paper.

In a large mixing bowl, add melted butter and brown sugar. Use a fork to mash together for 1 minutes

Add in egg and egg yolk and mix with fork until completely combined.

Add in milk, vanilla, peanut butter, sourdough discard, sea salt, baking soda, and baking powder. (Wait to add baking powder if you’re doing the optional cold ferment step below). Mix just until combined with a fork.

Add in flour and mix just until combined with a fork. The dough will be sticky, this is what you want! 

Optional – At this point you can either continue the recipe or place the dough, covered, in the fridge for 12-24 hours to long ferment for more sourdough fermentation benefits. When you’re ready to continue the recipe stir in the baking powder just before baking.

To continue the recipe use a 1 Tbsp (or 1.5 Tbsp) cookie scoop to scoop cookie dough onto the parchment lined pan. 

Use your hands to roll each scoop into a ball.

Make sure the cookies are 2 inches apart.

Use a fork to gently press each ball of cookie dough flat then do it again the other way for the iconic peanut butter cookie look. Dip your fork in brown sugar or flour if it keeps sticking to the cookies. 

Bake cookies at 350 degrees Fahrenheit for 8 minutes for slightly underbaked cookies or 10 minutes for fully baked fluffy cookies. Eitherway cookies will be soft when you pull them out, avoid overbaking.

Take cookies off the pan and place on a wire rack to cool. Enjoy!

How to Make Ahead (Freezer Cookie Dough)

If you’d like to make the cookie dough and freeze it, follow the recipe all the way through flattening the balls of dough on the sheet pans. Instead of popping sheet pans in the oven, pop them in the freezer for 2 hours to partially freeze.

Then place dough in an airtight container or baggie with parchment between layers. They’ll last for up to 3 months in the freezer unbaked. When you go to bake them, preheat your oven to 350 degrees Fahrenheit and bake straight from frozen for 10 minutes or until fully baked.

Our Favorite Way to Enjoy These Cookies

I love eating these cookies right out of the oven while they’re still warm! They go great with a glass of milk. My husband loves them with chocolate milk.

Storage Instructions

Once the cookies have completely cooled, place them in an airtight container. I like to use glass Pyrex storage containers for the best flavor. They’ll last about 1 week at room temperature.

Freezing and Thawing Instructions

Freezing Baked Cookies: Once cookies are completely cooled, place them in a preferably glass, freezer-safe container for the best flavor. They’ll last 3-6 months.

Thawing Baked Cookies: Let frozen cookies sit out on the counter for a few hours to thaw, or you can do this overnight in the fridge.

Freezing Cookie Dough: If you’d like to make the cookie dough and freeze it, follow the recipe all the way through flattening the balls of dough on the sheet pans. Instead of popping sheet pans in the oven, pop them in the freezer for 1-2 hours to partially freeze. Then place dough in an airtight container or baggie with parchment between layers. They’ll last for up to 3 months in the freezer unbaked. 

Thawing Cookie Dough: No need to thaw frozen cookie dough! Pop them straight into the oven from the freezer. Bake at 350 degrees Fahrenheit for 10 minutes or until fully baked.

My Favorite Way to Warm Cookies

When you want to warm a baked cookie, my favorite way is to pop it in the oven at 350 degrees for 2-4 minutes until warm. It keeps it soft! You could also do this in a toaster oven on the lowest temperature setting.

Frequently Asked Questions

More Sourdough Discard Cookie Recipes To Try

If you’re looking for more sourdough cookies, try a few of these:

• Mini Sourdough Chocolate Chip Pumpkin Cookies
• Sourdough Pistachio Chocolate Chip Cookies
• Sourdough Lofthouse Cookies (better than store-bought!)
• Cut Out Sourdough Sugar Cookies From Scratch
• Small-Batch Sourdough Chocolate Chip Blondies

If you made this recipe, give it a 5-star rating below and share a photo on your social media stories! Be sure to tag @plumbranchhome