Easy Sourdough Discard Peanut Butter Cookie Recipe

Peanut butter cookies usually taste great, but they can turn out dry fast if you’re not careful. This version fixes that problem using sourdough discard, which adds moisture and a soft bite without making the cookies taste “sour.”

It’s one of those recipes that feels like a cheat code once you try it.

And yes, they still have that classic peanut butter cookie vibe, just better, richer, and way less crumbly.

Table of Contents

What Makes This Recipe Shine

The biggest reason this recipe works is the sourdough discard, and I’m not saying that just to sound trendy. Discard adds a little acidity and extra hydration, which makes peanut butter cookies softer and slightly chewier without ruining the flavor. It basically saves them from that “dry sand cookie” situation.

The texture is honestly the best part. These cookies bake up with crisp edges, a soft middle, and that thick peanut butter richness that makes you go back for “one more” even when you swore you were done. They don’t fall apart in your hand either, which is a big win.

Flavor-wise, you get a deeper cookie taste than the usual peanut butter cookie. The discard gives it a mild tang in the background, kind of like how buttermilk makes pancakes taste better even though you don’t taste buttermilk directly. It’s subtle, but it adds character.

Another reason I love this recipe is how forgiving it is. You can use discard straight from the fridge, you can use natural peanut butter or regular, and the dough doesn’t act dramatic about it. It’s the kind of recipe that doesn’t punish you for being a normal human.

And let’s be real, sourdough discard recipes are basically therapy for anyone who hates wasting starter. Instead of dumping it, you turn it into warm cookies that smell like pure happiness, and that’s just a better life choice.

Ingredients You’ll Need

1/2 cup sourdough discard (unfed is fine, room temp or cold works)
1 cup peanut butter (creamy works best, chunky is fine too)
1/2 cup unsalted butter (softened, not melted)
3/4 cup brown sugar (packed, adds moisture and chew)
1/4 cup white sugar (helps crisp the edges)
1 large egg (binds everything together)
2 teaspoons vanilla extract (don’t skip it, it boosts the peanut flavor)
1 1/2 cups all-purpose flour (spooned and leveled)
1 teaspoon baking soda (gives lift and spread)
1/2 teaspoon baking powder (optional but helps fluff slightly)
1/2 teaspoon salt (especially important if peanut butter is unsalted)
1/2 cup chocolate chips (optional, but highly encouraged)
Extra sugar for rolling (optional, but gives that classic crackly top)

Step-by-Step Instructions

Step 1: Preheat and Prep Your Baking Setup

Preheat your oven to 350°F (175°C) and line two baking sheets with parchment paper. This keeps the cookies from sticking and helps them bake evenly without burning on the bottom.

If you don’t have parchment, use a silicone baking mat, but avoid greasing the pan. Peanut butter cookies already have plenty of fat, so extra grease can make them spread too much.

Step 2: Cream the Butter, Sugars, and Peanut Butter

In a large mixing bowl, add the softened butter, brown sugar, and white sugar. Mix until it looks fluffy and lighter in color, which usually takes about 1–2 minutes with a hand mixer.

Now add the peanut butter and mix again until everything looks smooth and thick. This step matters because it helps the cookies bake with a soft texture instead of feeling dense.

Step 3: Add the Egg, Vanilla, and Sourdough Discard

Crack in the egg and pour in the vanilla extract. Mix until fully combined, and don’t worry if the mixture looks a little glossy at first.

Next, add the sourdough discard and stir it in until the dough looks uniform. It might look slightly looser than typical peanut butter cookie dough, but that’s exactly what keeps the cookies soft later.

Step 4: Mix the Dry Ingredients Separately

In another bowl, whisk together the flour, baking soda, baking powder, and salt. Whisking helps distribute the baking soda evenly, which prevents random bitter bites.

This little extra step also keeps you from overmixing the dough later. Overmixing is how cookies end up tough, and nobody wants that kind of negativity.

Step 5: Combine Wet and Dry Ingredients

Slowly add the dry ingredients into the wet mixture. Stir gently until the flour disappears and the dough thickens into a scoopable texture.

Stop mixing the second everything looks combined. If you keep stirring like you’re trying to fight the dough into submission, you’ll lose that soft cookie texture.

Step 6: Add Mix-Ins (Optional but Delicious)

If you’re adding chocolate chips, fold them in now. I personally love semi-sweet chips because they balance the salty peanut butter flavor without making the cookies taste like candy bars.

You can also toss in chopped peanuts if you want extra crunch. Just don’t go wild with add-ins or the cookies won’t hold together as nicely.

Step 7: Scoop and Shape the Dough

Use a cookie scoop or tablespoon and roll the dough into balls about 1 1/2 inches wide. If you want the classic look, roll each ball lightly in sugar before placing it on the baking sheet.

Leave about 2 inches between each cookie. These cookies spread, not like crazy, but enough that they need breathing room.

Step 8: Press the Classic Fork Crisscross Pattern

Take a fork and gently press down on each dough ball, then press again in the opposite direction to create the crisscross pattern. Peanut butter cookie tradition demands it, and honestly, it also helps them bake evenly.

Don’t smash them flat like pancakes. Just press enough so the top flattens slightly and the lines show clearly.

Step 9: Bake Until Just Set

Bake for 10–12 minutes, depending on your oven. The edges should look lightly golden, but the centers should still look slightly soft when you pull them out.

This is the part where people panic and overbake them. Trust the process, because the cookies firm up as they cool.

Step 10: Cool Before Moving Them

Let the cookies cool on the baking sheet for about 5–7 minutes. If you try to move them right away, they’ll fall apart and you’ll feel personally attacked by your own dessert.

After that, transfer them to a cooling rack and let them finish setting up. The flavor actually gets better after they cool, which is kind of rude because you’ll want one immediately.

Common Mistakes to Avoid

One of the biggest mistakes is using peanut butter that’s too oily without mixing it properly. If you’re using natural peanut butter, stir it like your life depends on it before measuring. If you don’t, your dough can turn greasy and the cookies will spread too much.

Another issue is overbaking, which is basically the #1 way peanut butter cookies become dry and sad. These cookies should look slightly underdone in the middle when you take them out. If you wait until they look fully baked in the oven, they’ll be overcooked by the time they cool.

People also mess up by packing in too much flour. Flour is sneaky like that, because it compresses easily in the measuring cup. Spoon it in lightly and level it off, or you’ll end up with cookies that feel stiff instead of soft.

Using cold butter straight from the fridge is another common mistake. Cold butter won’t cream properly with sugar, and the dough won’t get that smooth, fluffy base that helps the cookies bake evenly. Softened butter gives you a much better texture, so it’s worth waiting 15 minutes.

And one more thing people do wrong is mixing the dough too aggressively once the flour goes in. That’s how gluten develops, and gluten is great for bread but annoying in cookies. Mix gently and stop early, even if you feel tempted to keep stirring.

Alternatives & Substitutions

If you want a slightly healthier version, you can swap half the flour for whole wheat flour. It gives the cookies a slightly nuttier taste and a denser bite, but it still works well with the sourdough discard. I wouldn’t use all whole wheat though, unless you like cookies that feel a bit more “serious.”

For the peanut butter, creamy is my go-to because it makes the dough smoother and the texture more consistent. Chunky peanut butter works too, but the cookies come out a little more rustic. Honestly, that’s not a bad thing if you’re into that homemade bakery-style look.

You can also replace the chocolate chips with chopped dark chocolate chunks. That gives you those melty pools of chocolate that look fancy even though you barely did anything. It’s the lazy genius option, and I fully support it.

If you’re dairy-free, swap the butter with a plant-based butter stick. Avoid margarine tubs because they contain more water and can mess up the cookie texture. Vegan butter sticks usually behave much closer to real butter, so you get a better bake.

For a fun flavor twist, try adding a pinch of cinnamon or even a tiny pinch of espresso powder. Espresso powder won’t make it taste like coffee, but it makes the peanut butter flavor deeper. It’s one of those “why does this taste so good?” upgrades.

And if you want to make them gluten-free, use a 1:1 gluten-free baking flour blend. The texture will be slightly more tender and crumbly, but the sourdough discard helps hold things together. Just make sure your discard is gluten-free too, or it defeats the whole point.

FAQ

Can you taste the sourdough discard in these cookies?

Not in a strong way, no. You might notice a slightly deeper flavor, but it doesn’t taste like sour bread or anything weird.

It’s more like the discard makes the cookie taste richer and less one-dimensional. Think “bakery cookie” instead of “basic peanut butter cookie.”

Do I need to feed my starter before using the discard?

Nope, unfed discard works perfectly here. In fact, this recipe is designed for that leftover discard you don’t want to waste.

If your discard smells super sharp or has been sitting for weeks, it might add a stronger tang. Fresh discard gives the best balanced flavor.

Can I chill the dough before baking?

Yes, and chilling actually makes the cookies thicker. If you chill the dough for 30–60 minutes, the cookies spread less and come out extra chewy.

If you’re planning ahead, you can chill it overnight too. Just let it sit out for 10 minutes so it’s easier to scoop.

Why did my cookies spread too much?

This usually happens if the butter was too warm or melted. It can also happen if your peanut butter was overly oily and not stirred properly.

Too little flour can cause spreading too, especially if you measured loosely. Chilling the dough for 20 minutes can fix this fast.

Can I freeze these cookies?

Absolutely, and they freeze really well. Once baked and cooled, store them in a freezer bag and they’ll stay good for about 2 months.

You can also freeze the dough balls and bake them straight from frozen. Just add 1–2 extra minutes to the baking time.

What’s the best way to store peanut butter sourdough cookies?

Store them in an airtight container at room temperature for about 4–5 days. They stay soft longer than most peanut butter cookies, which is honestly impressive.

If you want them extra chewy, toss a slice of bread in the container. It sounds weird, but it works like magic.

Can I make these cookies without eggs?

Yes, you can swap the egg for a flax egg (1 tablespoon ground flaxseed + 3 tablespoons water). Let it sit for 5 minutes before using.

The texture comes out slightly softer and less structured, but it still tastes great. It’s not identical, but it’s close enough to satisfy the cookie craving.

Final Thoughts

This sourdough discard peanut butter cookie recipe is one of those simple wins that feels way more impressive than it should. The cookies come out soft, rich, and full of peanut butter flavor without drying out like the classic version sometimes does. Plus, it gives you a solid excuse to stop wasting sourdough discard.

If you make them once, you’ll probably start saving discard just for this recipe. And honestly, that’s not a bad habit to have.