• Preheat oven to 375. In a stand mixer bowl with paddle attachment, add brown sugar, sugar, and butter and beat on medium speed until pale in color.
• Add in egg, vanilla, and sourdough starter. Mix until combined, scraping the sides occasionally.
• In a separate bowl, mix dry ingredients.
• While the mixer is on low speed, add dry ingredients about 1/3 at a time until the dough forms. Don't over-mix, or the cookies will not be tender.
• Mix in chocolate chips.
• Spoon onto a parchment-lined baking sheet. I like to use a scoop to make cookie dough balls.
• Bake at 375 degrees for about 10-12 minutes, or until they start to turn golden brown around the edges. Once done, I like to take them out and tap them onto the stove to make them go flat. Transfer to a wire rack to cool.

To Long Ferment:

• Create dough per the directions above. Add the dough to a large bowl with a lid, place in the refrigerator for up to 72 hours. It can be as short as you like, but I found that 72 hours gave it the perfect amount of tanginess and the best digestibility.
• Preheat oven to 375.
• Spoon your fermented dough onto a parchment-lined baking sheet and bake at 375 degrees for about 10-12 minutes. They will start to turn golden brown around the edges.
• Move to a wire rack to cool. Enjoy.