Peanut butter cookies are already a classic, but add sourdough starter and you get something extra special: a cookie that’s soft, chewy, and just a touch tangy. These cookies are simple to make, friendly for your leftover starter, and deliciously nostalgic. The edges stay tender, the centers stay plush, and the peanut butter flavor really shines.
If you love a bakery-style chew with a homemade feel, this recipe belongs in your rotation. Let’s make a batch you’ll want to keep on repeat.
What Makes This Special
- Soft and chewy texture: The sourdough starter adds moisture that keeps these cookies tender for days.
- Balanced flavor: Peanut butter richness meets a gentle tang from the starter—subtle but memorable.
- Great use of discard: Put your unfed sourdough starter to work instead of tossing it.
- No chill time required: The dough comes together easily and bakes right away.
- Foolproof for weeknights: Straightforward steps and everyday ingredients keep things low stress.
Ingredients
- 1/2 cup (113 g) unsalted butter, softened
- 1 cup (240 g) creamy peanut butter (no-stir works best)
- 3/4 cup (150 g) granulated sugar
- 1/2 cup (100 g) light brown sugar, packed
- 1 large egg, room temperature
- 1 teaspoon vanilla extract
- 1 cup (240 g) sourdough starter discard, unfed
- 1 1/2 cups (190 g) all-purpose flour
- 1 teaspoon baking soda
- 1/2 teaspoon baking powder
- 1/2 teaspoon fine sea salt
- Optional: 1/2 cup (85 g) peanut butter chips or chocolate chips
- Optional: Extra granulated sugar for rolling
How to Make It
- Prep the oven and pans: Heat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
- Cream the fats and sugars: In a large bowl, beat the softened butter, peanut butter, granulated sugar, and brown sugar until light and fluffy, about 2 minutes.
This step helps create that tender, chewy texture.
- Add the egg and vanilla: Mix in the egg and vanilla until smooth. Scrape down the bowl so everything blends evenly.
- Incorporate the sourdough starter: Stir in the sourdough discard until fully combined. The batter may look silky and slightly looser—that’s perfect.
- Whisk dry ingredients: In a separate bowl, whisk the flour, baking soda, baking powder, and salt.
- Combine wet and dry: Add the dry ingredients to the wet mixture.
Mix on low just until no dry streaks remain. If using chips, fold them in now. Do not overmix.
- Portion the dough: Scoop 1 1/2-tablespoon portions (a medium cookie scoop) and roll into balls.
For a classic look, gently roll each ball in granulated sugar. Place on the prepared sheets, leaving about 2 inches between cookies.
- Optional crisscross: Lightly press each dough ball with a fork in a crisscross pattern. Don’t flatten too much if you prefer a chewier, thicker cookie.
- Bake: Bake for 9–12 minutes, until the edges look set and the centers are slightly underbaked.
The cookies will puff and then settle as they cool.
- Set and cool: Let the cookies rest on the baking sheet for 5 minutes, then transfer to a rack to cool. This helps lock in that soft center.
How to Store
- Room temperature: Keep cookies in an airtight container for 4–5 days. Slip in a slice of bread to keep them soft.
- Freezer: Freeze baked cookies in a zip-top bag for up to 3 months.
Thaw at room temp.
- Make-ahead dough: Scoop dough balls, freeze on a sheet until firm, then store in a bag for up to 2 months. Bake from frozen, adding 1–2 minutes to the bake time.
Benefits of This Recipe
- Reduces waste: Uses unfed sourdough starter you’d otherwise discard.
- Great texture payoff: The starter adds moisture and chew without making the cookies bready.
- Reliable and forgiving: The dough isn’t fussy and doesn’t need chilling.
- Simple pantry staples: No special equipment or hard-to-find ingredients.
- Flexible sweetness: Easy to adjust sugar or add mix-ins without losing structure.
Pitfalls to Watch Out For
- Using natural peanut butter that separates: It can make the dough oily or crumbly. If you use it, mix extremely well and consider adding 1–2 tablespoons extra flour.
- Overbaking: Pull the cookies when the centers still look a touch soft.
They firm up as they cool.
- Overmixing the dough: Stir just until combined to avoid tough cookies.
- Too-warm butter: If the butter is melted, the cookies can spread too much. Aim for soft, not greasy.
- Very runny starter: If your discard is thin, the dough may be sticky. Add 1–2 tablespoons flour until it scoops cleanly.
Recipe Variations
- Chocolate chip swirl: Fold in 1/2–3/4 cup chocolate chips or chunks for a peanut butter cup vibe.
- Salted finish: Sprinkle with flaky sea salt right after baking for a sweet-salty pop.
- Crunchy peanut butter: Swap in crunchy peanut butter for added texture.
- Peanut butter blossom style: Skip the fork marks, roll in sugar, bake, then press a chocolate kiss in the center while warm.
- Gluten-free test: Use a 1:1 gluten-free all-purpose blend with xanthan gum.
The cookies may spread slightly less; monitor bake time.
- Extra peanut: Add 1/2 cup roasted peanuts for crunch, or roll dough balls in chopped peanuts before baking.
- Maple note: Replace 1/4 cup of granulated sugar with maple syrup and add 1 tablespoon extra flour to balance moisture.
FAQ
Can I use active, fed starter instead of discard?
Yes. Active starter works fine and won’t change the rise much since this is a quick cookie. The flavor may be a touch milder.
Use the same amount.
Do I have to include both baking soda and baking powder?
They do different jobs. Baking soda reacts with the slight acidity from the starter and peanut butter, while baking powder gives extra lift. Using both keeps the cookies soft and not too dense.
Why did my cookies spread too much?
The butter may have been too warm, the starter too thin, or the oven not fully preheated.
Chill the dough for 20 minutes, add a tablespoon or two of flour if it’s very sticky, and be sure your oven is at 350°F before baking.
Can I make them less sweet?
You can reduce the granulated sugar by 2–3 tablespoons without hurting texture. Keep the brown sugar for moisture and chew. Taste the dough and adjust to your preference.
Is chunky peanut butter okay?
Absolutely.
It adds nice texture. If your chunky peanut butter is very thick, you can loosen the dough with a teaspoon of milk or reduce the flour by a tablespoon.
How do I keep them soft the next day?
Store in an airtight container with a slice of sandwich bread or a few marshmallows. The cookies absorb a bit of moisture and stay chewy.
Can I make them dairy-free?
Use a good dairy-free butter stick (not a spread) and check that your chocolate chips, if using, are dairy-free.
The texture stays very close to the original.
In Conclusion
Soft Chewy Sourdough Peanut Butter Cookies bring together the comfort of a classic and the character of sourdough. They’re easy to mix, bake up beautifully, and stay tender for days. Keep the ingredients simple, watch the bake time, and you’ll have a tray of cookies that taste like home—with a little something extra.
Whether you’re baking for a crowd or just treating yourself, this recipe is a keeper.
Soft Chewy Sourdough Peanut Butter Cookies – Comforting, Tangy, and Rich
Ingredients
- 1/2 cup (113 g) unsalted butter, softened
- 1 cup (240 g) creamy peanut butter (no-stir works best)
- 3/4 cup (150 g) granulated sugar
- 1/2 cup (100 g) light brown sugar, packed
- 1 large egg, room temperature
- 1 teaspoon vanilla extract
- 1 cup (240 g) sourdough starter discard, unfed
- 1 1/2 cups (190 g) all-purpose flour
- 1 teaspoon baking soda
- 1/2 teaspoon baking powder
- 1/2 teaspoon fine sea salt
- Optional: 1/2 cup (85 g) peanut butter chips or chocolate chips
- Optional: Extra granulated sugar for rolling
Instructions
- Prep the oven and pans: Heat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
- Cream the fats and sugars: In a large bowl, beat the softened butter, peanut butter, granulated sugar, and brown sugar until light and fluffy, about 2 minutes. This step helps create that tender, chewy texture.
- Add the egg and vanilla: Mix in the egg and vanilla until smooth. Scrape down the bowl so everything blends evenly.
- Incorporate the sourdough starter: Stir in the sourdough discard until fully combined. The batter may look silky and slightly looser—that’s perfect.
- Whisk dry ingredients: In a separate bowl, whisk the flour, baking soda, baking powder, and salt.
- Combine wet and dry: Add the dry ingredients to the wet mixture. Mix on low just until no dry streaks remain. If using chips, fold them in now. Do not overmix.
- Portion the dough: Scoop 1 1/2-tablespoon portions (a medium cookie scoop) and roll into balls. For a classic look, gently roll each ball in granulated sugar. Place on the prepared sheets, leaving about 2 inches between cookies.
- Optional crisscross: Lightly press each dough ball with a fork in a crisscross pattern. Don’t flatten too much if you prefer a chewier, thicker cookie.
- Bake: Bake for 9–12 minutes, until the edges look set and the centers are slightly underbaked. The cookies will puff and then settle as they cool.
- Set and cool: Let the cookies rest on the baking sheet for 5 minutes, then transfer to a rack to cool. This helps lock in that soft center.
