Preheat oven to 350F and move the rack to the middle position. Line a large baking sheet with parchment paper or a Silpat silicone mat.

Add the brownie mix, flour, vegetable oil, eggs, and peppermint extract to a large mixing bowl. Using an electric hand mixer, mix until everything is combined.

Stir in the chocolate chips.

Form the cookie batter into 2" balls. Add them to your baking sheet leaving at least an inch or so gap. I usually bake 2 batches. Bake each batch for 12-14 minutes. 

Meanwhile, if you want to top the cookies with crushed candy canes, crush them in a ZipLoc using a rolling pin until the pieces are the size you want.

Once cookies are done, take them out of the oven and let them cool on the baking sheet for a few minutes before transferring them to a wire rack. At this point, you can melt some more chocolate chips. Start with 1/4 cup chocolate chips. I melt it in 30 second increments in the microwave and use a fork to drizzle it onto the cookies. I then sprinkle the crushed candy canes on top.

Once cookies have cooled completely, transfer them to a sealed container. Cookies will keep for a few days.