Preheat oven to 325 degrees. Spray an 8x8 pan with non-stick spray or line with parchment paper and set aside.
Add the 2 cups of chopped dark chocolate and the butter (cut into cubes for easier melting) into a microwavable bowl and heat in 30 second intervals, whisking in between, until fully melted and smooth. Set aside.
In a mixing bowl, beat the eggs until smooth. Add the sugar and vanilla and mix until smooth.
Add the melted chocolate/butter mixture and mix until combined.
Add the flour, salt, and baking powder and gently stir in by hand until completely mixed.
Pour into prepared pan and bake for 25 minutes. Meanwhile, crush the peppermint candies in a food processor. The amount is totally up to you - I used about 15 mini candy canes.
After the 25 minutes, remove brownies from the oven and sprinkle the crushed peppermint over the top and LIGHTLY press them in with a spatula. Return to the oven and bake for 22 more minutes. When they're done, the center will be mostly set and a toothpick inserted in the middle will have some gooey brownie crumbs on it (it shouldn't be liquid though).
Let cool completely before decorating with the chocolate (let cool on the counter for a bit first, then cover with foil and refrigerate to speed things up)
Add some chocolate shavings or melted chocolate to the top for decoration (I used white chocolate shavings and melted dark chocolate).