Preheat your oven to 350°F (175°C).
In a mixing bowl, cream together the softened butter, brown sugar, and granulated sugar.
Add the sourdough starter and vanilla extract to the mixture, stirring until well combined.
In a separate bowl, whisk together the flour, baking soda, and salt.
Gradually add the dry ingredients to the wet mixture, stirring gently until just combined.
Fold in the chocolate chips using a spatula.
Scoop tablespoon-sized balls of dough onto a lined baking sheet, spacing them about 2 inches apart.
Bake in the preheated oven for 10-12 minutes until golden around the edges.
Remove from the oven and let cool on the baking sheet for 5 minutes before transferring to a wire rack.
Enjoy warm or store for later!