Sourdough Chocolate Chip Cookies

Ingredients:

• 1.5 cups premium flour
• 0.5 tsp baking powder
• 1/4 teaspoon of baking soda
• 3/4 teaspoon coarse salt
• 6 tbsp unsalted butter, softened
• 2/3 cup firmly packed dark brown sugar
• 0.5 cup granulated sugar
• 1 large egg, lightly beaten
• 1 tsp vanilla extract
• 0.5 cups of excess sourdough starter 100% moisture (equal proportions of flour and water)
• 1 cup chopped semisweet chocolate (about 140 g)

Preparation:

1. In a medium bowl, combine the flour, baking powder, baking soda, and salt. In a large bowl, beat the butter with the brown and white sugars with a mixer on medium-high speed until fluffy, about 5 minutes. Add the egg and vanilla extract and beat until creamy, about 1 minute. Stir in the starter, scraping down the sides of the bowl as needed, until fully incorporated, about 1 more minute. Reduce the mixer speed to low and add the flour mixture. Once the flour is moistened, increase the speed to medium and knead until smooth. Stir in the chocolate chips with a spatula, then refrigerate the dough, covered, for 8 to 24 hours.
2. When you're ready to bake the cookies, preheat the oven to 190°C.
3. Drop the batter by the heaping tablespoon (30-45 g) onto two large ungreased baking sheets, spacing them 2 inches (5 cm) apart. You may need to bake in two batches. Bake until the edges are light golden and just set but the tops are still soft, 12-18 minutes, rotating the baking sheets and rotating them halfway through. Let cool for a few minutes, then transfer the cookies with a spatula to a wire rack to cool completely. Store in a tightly sealed container for up to 5 days..