Step 1

In a large bowl, combine the softened butter and sugars. (Make sure the butter is soft enough to mix with the sugar by hand.)

Step 2

Add the egg to the mixture, stirring until incorporated.

Step 3

Stir in the sourdough starter and vanilla extract.

Step 4

Add the flour, salt, and baking soda, careful to not overmix.

Step 5

Finally, incorporate the chocolate chips and let the dough refrigerate for 15 minutes or refrigerate up to overnight. (I have made them without refrigeration and they get more cake-like in texture.)

Step 6

When ready to bake the cookies, preheat the oven to 350°F. (Let the refrigerated cookies come to room temperature.)

Step 7

Drop spoonfuls (2-3 tablespoons) of dough onto a parchment-lined baking sheet. (I use a 3 tablespoon ice cream scoop.) Bake 8-10 minutes for a cake-like cookie. Bake 6-8 minutes for a chewier cookie. (My recommendation!) The cookie MAY appear a little wet in the center and that is ok. It will continue to bake and be cooked throughout after being out of the oven for a few minutes.