Preheat oven to 350° F and grease an 8×8 nonstick pan with butter and set aside.
In a double boiler, melt chocolate chips and butter over low heat stirring occasionally until fully combined. Remove from the double boiler. Whisk in the cocoa.
In a separate bowl, whisk together eggs and sugar with a hand mixer at medium-high speed.
Add the peppermint extract, vanilla, and salt and whisk on low until combined.
Slowly pour the melted chocolate mixture into the egg mixture.
Add the flour and mix with a wooden spoon until fully incorporated.
Add chopped peppermint bark. Mix until the pieces are evenly distributed.
Pour the batter into the prepared pan, spreading it into the corners and leveling the top with a rubber spatula.
Bake 30-35 minutes, or until the top is shiny and a toothpick inserted into the center comes out clean. Do not over bake.
Set aside to cool. Now make your frosting.
While the brownies cool, start on the frosting: