Mix Dry Ingredients:
In a medium bowl, whisk together flour, baking soda, and salt. Set aside.
Prepare Wet Mixture:
In a large mixing bowl, whisk together melted butter, brown sugar, and white sugar until smooth and creamy.
Add Eggs and Vanilla:
Stir in the egg, egg yolk, and vanilla extract until fully combined.
Combine and Fold:
Add the dry ingredients to the wet ingredients, mixing gently until just combined. Fold in the chocolate chips.
Chill the Dough:
Cover the bowl and refrigerate for 30–60 minutes to help the cookies bake thicker and softer.
Bake:
Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper and scoop 2 tablespoons of dough per cookie. Bake for 9–11 minutes or until the edges are golden brown but the centers still look slightly soft.
Cool and Serve:
Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack. Enjoy warm or store in an airtight container for up to 5 days.