Preparation Steps

• Chill the dough for at least 3 hours or overnight for thicker cookies.
• Beat the butter, granulated sugar, and brown sugar together in a large bowl until fluffy.
• Add the egg and vanilla, then beat until combined. Scrape down the bowl as needed.
• In a separate bowl, whisk flour, cocoa powder, baking soda, and salt together.
• With the mixer on low, slowly add the dry ingredients to the wet mixture.
• Beat on low until combined, then switch to high speed and add milk and chocolate chips.
• Cover the dough and chill in the refrigerator.
• Allow cookie dough to sit at room temperature for 10-20 minutes before baking.
• Preheat oven to 350°F (177°C) and line baking sheets.
• Scoop dough into balls and arrange on baking sheets.
• Bake for 11-12 minutes until edges are set and centers are soft.
• Cool cookies for 5 minutes on the baking sheet before transferring to a cooling rack.