Instructions

1. Ensure all ingredients are at room temperature, especially the butter, to achieve optimal mixing consistency.
2. In a large mixing bowl, cream the softened unsalted butter and powdered sugar together using an electric mixer until light and fluffy, approximately 3-4 minutes.
3. Add vanilla extract to the butter-sugar mixture and mix until fully incorporated.
4. In a separate bowl, sift together all-purpose flour, dark cocoa powder, and salt to remove any lumps and ensure even distribution.
5. Gradually add the dry ingredient mixture to the butter mixture, mixing on low speed until just combined. Do not overmix.
6. Fold in dark chocolate chunks gently using a spatula, distributing them evenly throughout the dough.
7. Shape the cookie dough into a log approximately 2 inches in diameter, wrapping tightly in plastic wrap.
8. Refrigerate the dough log for at least 1 hour to firm up, which helps cookies maintain shape during baking.
9. Preheat the oven to 350°F (175°C) and line two baking sheets with parchment paper.
10. Remove dough from refrigerator and slice into 1/4-inch thick rounds using a sharp knife.
11. Place cookie slices about 1 inch apart on prepared baking sheets.
12. Bake for 12-15 minutes, or until edges are lightly set and bottoms are slightly golden.
13. Remove from oven and let cookies cool on baking sheet for 5 minutes before transferring to a wire rack.
14. Allow cookies to cool completely before serving or storing in an airtight container.