Ingredients

Equipment Needed

• •Stand mixer or hand mixer
• •2-tablespoon cookie scoop
• •Two rimmed baking sheets
• •Wire cooling rack

Instructions

1. 1

   Whisk dry ingredients

   In a medium bowl, whisk together the flour, baking soda, and fine sea salt until thoroughly combined. The baking soda is critical here. It reacts with the acidity in your sourdough discard to create lift. Set aside.

   Weigh your flour if possible. Scooped flour can vary by 30% and throw off the texture completely.
2. 2

   Cream butter and sugars

   In a large bowl or stand mixer fitted with the paddle attachment, beat the softened butter with both sugars on medium speed for 3 to 4 minutes. You're looking for a pale, fluffy mixture that has roughly doubled in volume. Scrape down the sides halfway through. This aeration is the foundation of your cookie's texture.

   Dark brown sugar contains more molasses than light, which adds moisture and chewiness. Don't substitute light brown sugar if you want that characteristic dense center.
3. 3

   Add eggs and vanilla

   Add the eggs one at a time, beating well after each addition until fully incorporated. The mixture may look slightly curdled after the first egg. That's fine. It will smooth out. Add the vanilla extract and beat for another 30 seconds. The batter should look smooth and glossy.

4. 4

   Incorporate sourdough discard

   Add the sourdough discard all at once and mix on low speed until just combined, about 30 seconds. The discard will thin the batter noticeably. Don't worry. The flour will bring it back. Give your discard a good stir before measuring since it tends to separate in the jar.

   Cold discard straight from the refrigerator works perfectly. No need to bring it to room temperature or feed it first.
5. 5

   Add flour mixture

   Add the flour mixture in two additions, mixing on low speed just until the last streaks of flour disappear. Overmixing develops gluten and creates tough cookies. Stop the mixer while you can still see a few traces of flour, then finish incorporating by hand with a rubber spatula.

6. 6

   Fold in chocolate

   Fold in the chocolate chips with your spatula, distributing them evenly throughout the dough. The dough will be soft and sticky at this point, which is exactly right. Resist the urge to add more flour.

7. 7

   Chill the dough

   Cover the bowl tightly with plastic wrap and refrigerate for at least 2 hours, or overnight. This rest is not optional. Chilling solidifies the butter for better spreading control and allows the flour to fully hydrate. The flavors meld and deepen. The sourdough tang becomes more pronounced. Patience here pays dividends.

   For the most complex flavor, chill the dough for 24 to 72 hours. The longer rest allows the sourdough cultures to continue working slowly, building depth that shorter rests cannot achieve.
8. 8

   Preheat and prepare

   When ready to bake, position racks in the upper and lower thirds of your oven and preheat to 375°F. Line two baking sheets with parchment paper. Remove dough from refrigerator while oven heats.

9. 9

   Portion the dough

   Scoop dough into 2-tablespoon portions (roughly 45g each) and place on prepared sheets, leaving 3 inches between cookies. They spread considerably. A cookie scoop ensures uniform size and even baking. Roll each portion into a rough ball, then gently flatten the top slightly with your palm.

   For bakery-style cookies with irregular edges and pools of chocolate, tear each dough ball in half and smash the two halves back together with the ragged edges facing up.
10. 10

    Bake until golden

    Bake for 10 to 12 minutes, rotating the pans front to back and switching racks halfway through. The cookies are done when the edges are golden brown and set but the centers still look slightly underdone and puffy. They will continue cooking on the hot pan. Pull them when they look not quite done. This is the secret to chewy centers.

11. 11

    Finish and cool

    Remove from oven and immediately sprinkle each cookie with a few flakes of finishing salt while the chocolate is still molten. Let cookies cool on the baking sheet for 5 minutes, during which they'll deflate slightly and the centers will set. Transfer to a wire rack to cool completely. Or eat them warm, which is your right as the baker.

Chef Tips

• •Your discard's age affects the final flavor. Week-old discard produces cookies with noticeable tang. Freshly fed discard that's been sitting just a day creates subtler complexity. Neither is wrong, just different. Experiment to find your preference.
• •For maximum chocolate impact, use a mix of chips and roughly chopped chocolate bars. The chips hold their shape; the chopped pieces create those coveted chocolate streaks and pools.
• •These cookies freeze beautifully as portioned dough balls. Freeze on a sheet pan, then transfer to a freezer bag. Bake directly from frozen at 375°F for 13 to 15 minutes. No thawing required.
• •If your discard is extremely sour and liquid, use a bit less. If it's thick and paste-like, you can use the full amount. Consistency varies wildly between starters, which is part of the charm.

Advance Preparation

• •Dough must chill at least 2 hours and can rest in the refrigerator for up to 5 days, improving in flavor each day.
• •Portioned dough balls freeze for up to 3 months. Label with date and baking temperature.
• •Baked cookies keep in an airtight container at room temperature for 5 days, though they rarely last that long.

Frequently Asked Questions

Nutrition Information

1 serving (about 42g)