Preheat oven to 350°F. Line a baking sheet with parchment paper.
Add the brownie mix, butter, flour, cocoa powder, eggs, corn syrup and baking soda to a large bowl. Mix to combine. (I used a hand mixer).
Stir in the chocolate chips.
Use a ¼ cup to portion the cookies into balls. Bake for 11-12 mins. The edges will be set and the tops will be crackly.
Some cookies may have uneven edges. To fix this, use a very large round biscuit cutter or cookie cutter and immediately after removing the cookies from the oven, gently use the cutter in a circular motion around the cookies to tuck in the edges (think hula hoop motion). We don’t want to cut the cookie. We just want to make the cookies uniformly circle before they set. For a video of what this looks like, check out my Instagram page.
Let cookies cool on the pan for 10 minutes before transferring to a wire rack to cool completely.
Notes
Important! Sometimes a brownie box will claim it is 18.3 oz, but it is best to measure the brownie mix on your own kitchen scale to double check and make sure it is in fact 18.3 oz!Store the cookies in an airtight container or Ziplock bag at room temperature for 4-5 days.The dough will be softer than a traditional cookie dough because we are trying to make a fudgy brownie cookie!If your cookies are flat, it could be a few reasons, you might need to add an additional tablespoon or two of flour. And make sure you have an oven thermometer. The oven needs to be at 350°F in order for the cookies to turn out right!