I used a food processor for the first time this year to chop the candies, you can always use the old-fashioned "bash 'em with a hammer" method, but this was quicker and more uniform. Process for about 10 seconds until most of the mints are dust, but there are still a few pea sized chunks in there, too. I used Trader Joe's brand peppermints because they don't have artificial colorings or flavors. They are smaller, though, so I used about 35 candies.
Yield: 53 cookie scoop size cookies, 44 if you follow the directions
1/2 C stick butter, softened
1/2 C sugar
1/2 C firmly packed brown sugar
1 tsp vanilla extract
2 1/4 C all-purpose flour
1 tsp baking powder
3/4 tsp baking soda
1/4 tsp salt
1/4 C plus 1 Tbs unsweetened cocoa
2/3 C finely crushed round peppermint candies (about 30 candies or 8 candy canes)
1/2 C chocolate chips
You definitely want these to be on some sort of barrier instead of relying on cooking spray or any magical non-stick properties your pan may possess. They can be super sticky!
I really like these especially with the smaller pieces. The kids love them with hot chocolate!