Preheat Oven:
Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper or a silicone mat.
Mix Wet Ingredients:
In a mixing bowl, whisk together the melted butter, brown sugar, and granulated sugar until smooth. Add the egg yolk and vanilla extract, whisking until well combined.
Combine Dry Ingredients:
Add the flour, baking soda, and salt to the wet ingredients. Mix until just combined, being careful not to overmix.
Add Chocolate Chips:
Fold in the chocolate chips, ensuring they are evenly distributed throughout the dough.
Portion the Dough:
Scoop the dough into six equal portions and place them on the prepared baking sheet, spacing them about 2 inches apart.
Bake:
Bake for 9-11 minutes, or until the edges are lightly golden. The centers may look slightly underbaked, but they will set as they cool.
Cool and Serve:
Let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.