I make these sourdough peanut butter cookies almost every week — they’re fast, forgiving, and the discard gives them a subtle tang that lifts the peanut flavor. Crisp at the edges, soft in the middle, and rolled in sugar for a crackly finish, they’re the kind of cookie that disappears at a party and earns recipe requests. If you keep a starter, this is a delicious way to use discard and avoid waste.
Why you’ll love this dish
These cookies combine everyday pantry ingredients into a comforting, slightly tangy peanut butter cookie that’s child-friendly and great for weekday baking. They’re budget-friendly, quick to mix (no chilling required), and the sourdough discard adds moisture and a gentle complexity you won’t get from a standard peanut butter cookie.
“The best peanut butter cookie I’ve made — crunchy edges, tender center, and the faint tang from the discard is brilliant.” — a happy taster
They work well for lunchboxes, bake sales, or a last-minute dessert when friends pop by.
How this recipe comes together
Quick overview so you know what to expect:
- Cream the butter, sugars, and peanut butter until light and smooth.
- Incorporate vanilla, the sourdough discard, and an egg to bind.
- Fold in the dry ingredients (flour, baking soda, salt) just until combined.
- Scoop, roll in sugar, press with a fork for the classic pattern, and bake until edges are lightly browned.
- Let cookies set on the baking sheet a few minutes before moving to a rack.
This recipe is straightforward: mixing, shaping, and a short bake at 325°F produces cookies that are soft inside with crisp edges.
What you’ll need
- 113 grams unsalted butter, softened (room temperature)
- 100 grams cane sugar (in dough)
- 150 grams brown sugar
- 170 grams smooth or creamy peanut butter (do NOT use chunky or natural — natural separates and will change texture)
- 8 grams vanilla extract
- 56 grams sourdough discard (unfed discard is fine)
- 1 large egg
- 240 grams all-purpose flour
- 3 grams baking soda
- 4 grams salt
- 50 grams cane sugar (for coating)
Notes/substitutions:
- Brown sugar adds chew and moisture; you can use light or dark brown depending on your taste.
- If you must use natural peanut butter, stir thoroughly and reduce any added liquid; expect a slightly denser cookie.
- For a dairy-free version, swap the butter for a solid baking margarine and confirm the peanut butter is compliant.
Directions to follow
- Preheat the oven to 325°F (163°C). Line two baking sheets with parchment paper and set aside.
- In a large bowl, cream together the softened butter, 100 g cane sugar, and 150 g brown sugar until light and slightly fluffy.
- Add 170 g smooth peanut butter and 8 g vanilla. Mix until fully incorporated.
- Stir in 56 g sourdough discard and 1 egg. Mix until no visible yolk or streaks of discard remain.
- In a separate bowl, whisk together 240 g all-purpose flour, 3 g baking soda, and 4 g salt.
- Fold the dry ingredients into the wet mixture just until no dry flour pockets remain. Do not overmix.
- Use a 1½-tablespoon cookie scoop (medium) to portion dough. Place scoops at least 2 inches apart on the prepared sheets to allow spreading.
- Pour 50 g cane sugar into a small bowl. Roll each dough ball in the sugar to coat the outside.
- Place sugared dough balls on the sheet and use a fork to gently flatten each one, creating the traditional crisscross grid pattern.
- Bake 10–12 minutes, or until edges are lightly browned but centers still look slightly soft.
- Let cookies cool on the baking sheet for about 5 minutes — they set as they cool. Moving them too soon risks breaking.
- Transfer to a wire rack to cool completely before storing or serving.
Best ways to enjoy it
- Serve warm with a cold glass of milk — the classic combo.
- Pair with a scoop of vanilla ice cream for an easy dessert sandwich.
- For a grown-up twist, serve alongside coffee or espresso; the sourdough tang complements roasted coffee notes.
- Plate several on a cookie board with chocolate-covered pretzels and dried fruit for a casual dessert spread.
Keeping leftovers fresh
- Room temperature: Store completely cooled cookies in an airtight container for up to 1 week. Place a slice of bread in the container to help maintain softness (replace as it dries).
- Refrigeration: Not necessary and can dry cookies out faster; only refrigerate if your kitchen is very warm.
- Freezing: Freeze baked cookies in a single layer on a tray, then transfer to a freezer bag or container for up to 3 months. Thaw at room temperature or warm briefly in a 250°F oven for a few minutes.
- Food safety: Baked cookies with egg are safe at room temperature for typical storage durations; discard if you notice mold or an off smell.
Pro chef tips
- Softened butter: Pull the butter out 30–45 minutes before mixing. If it’s too warm, cookies will spread excessively.
- Scoop and roll consistently: Using a cookie scoop gives uniform baking; rolling in sugar creates a crisp, slightly crunchy exterior.
- Don’t overwork the dough: Fold until combined. Overmixing develops gluten and leads to tougher cookies.
- Adjust baking time by sheet placement: If your oven runs hot on top, rotate sheets halfway through baking for even browning.
- Use fresh baking soda: Old soda loses leavening power and yields flat cookies — test by mixing a pinch with vinegar; it should fizz.
Creative twists
- Chocolate chip: Fold in 80–100 g semi-sweet chocolate chips for classic combo.
- Sea salt finish: Sprinkle a tiny pinch of flaky sea salt on each cookie after pressing and before baking.
- Spiced version: Add ½ teaspoon ground cinnamon and a pinch of nutmeg for warmth.
- Vegan swap: Use vegan butter and a flax “egg” (1 tbsp ground flax + 3 tbsp water) — texture will be slightly different but still tasty.
- Nutty crunch: Stir in 80 g finely chopped roasted peanuts for texture (if using, reduce regular peanut butter slightly).
Your questions answered
Q: Can I use natural peanut butter or crunchy peanut butter?
A: Natural peanut butter (oil-separated) can change the dough’s texture and may make cookies denser; use well-stirred natural if you must and expect a different result. Crunchy will add texture but recipe calls for smooth for consistent spread.
Q: Do I have to use sourdough discard?
A: You can omit the discard and replace the 56 g with an extra tablespoon of butter and a splash of milk if needed. The discard adds moisture and a subtle tang that improves flavor, so omit only if necessary.
Q: Can I freeze the raw dough?
A: Yes. Scoop balls onto a tray, freeze until solid, then transfer to a freezer bag. Bake from frozen — add 1–2 minutes to the bake time.
Q: How long does this take from start to finish?
A: About 25–35 minutes total: 10–15 minutes mixing and scooping, plus 10–12 minutes baking per batch and a short cooling rest.
Q: Are these safe with the raw egg in the dough?
A: The dough contains raw egg, but cookies are fully baked. Avoid tasting raw dough. If egg safety is a concern, use pasteurized eggs.
Conclusion
If you like peanut butter cookies with a little extra depth, this sourdough discard version is a simple upgrade worth trying. For more inspiration and variations on sourdough peanut butter cookies, check out Best Chewy Sourdough Peanut Butter Cookies • Heartbeet Kitchen and Sourdough Peanut Butter Cookies – Little Spoon Farm.
Sourdough Peanut Butter Cookies
Ingredients
For the cookie dough
- 113 grams 113 grams unsalted butter, softened Make sure butter is at room temperature.
- 100 grams 100 grams cane sugar (in dough)
- 150 grams 150 grams brown sugar Use light or dark brown sugar depending on taste.
- 170 grams 170 grams smooth or creamy peanut butter Do NOT use chunky or natural peanut butter.
- 8 grams 8 grams vanilla extract
- 56 grams 56 grams sourdough discard Unfed discard is fine.
- 1 large 1 large egg
- 240 grams 240 grams all-purpose flour
- 3 grams 3 grams baking soda
- 4 grams 4 grams salt
- 50 grams 50 grams cane sugar (for coating)
Instructions
Preparation
- Preheat the oven to 325°F (163°C). Line two baking sheets with parchment paper and set aside.
- In a large bowl, cream together the softened butter, 100 g cane sugar, and 150 g brown sugar until light and slightly fluffy.
- Add 170 g smooth peanut butter and 8 g vanilla. Mix until fully incorporated.
- Stir in 56 g sourdough discard and 1 egg. Mix until no visible yolk or streaks of discard remain.
- In a separate bowl, whisk together 240 g all-purpose flour, 3 g baking soda, and 4 g salt.
- Fold the dry ingredients into the wet mixture just until no dry flour pockets remain. Do not overmix.
- Use a 1½-tablespoon cookie scoop to portion dough. Place scoops at least 2 inches apart on the prepared sheets.
- Roll each dough ball in 50 g cane sugar to coat the outside.
- Use a fork to gently flatten each one, creating the traditional crisscross grid pattern.
- Bake for 10–12 minutes, or until edges are lightly browned but centers still look slightly soft.
- Let cookies cool on the baking sheet for about 5 minutes before transferring to a wire rack to cool completely.
