Preheat oven to 350 °F (177 °C). Line baking sheets with silicone baking mats or parchment paper. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, cream together butter, brown sugar, and granulated sugar until creamy and fluffy. Add in the pudding mix, eggs, and vanilla extract. Beat well until incorporated.
1 cup unsalted butter, 3/4 cup dark brown sugar, 1/4 cup granulated sugar, 3.4 ounce package of chocolate fudge pudding mix, 2 large eggs, 1 teaspoon vanilla extract
In a medium bowl, whisk together flour, cocoa powder, baking soda, and salt.
2 1/4 cups all purpose flour, 1/4 cup Dutch-processed cocoa powder, 1 teaspoon baking soda, 1/2 teaspoon salt
Slowly add in the dry ingredients until just combined. Fold in the peppermint chips with a spatula.
1 cup Andes peppermint crunch baking chips
Drop cookies onto baking sheet with a cookie scoop (I used a medium cookie scoop) and bake for 10 minutes or until slightly golden around the edges.
Remove from oven and let cool on baking sheet for 5 minutes. Transfer to wire cooling racks to cool completely.