01 -
In a medium pot, melt the butter with chocolate pieces over medium heat. Stir the whole time for about 5 minutes. You can also do this in a microwave bowl, heating for 20 seconds at a time. Move the mix to a big bowl and let it cool down for 10 minutes.
02 -
Put your oven rack in the bottom third spot and heat to 177°C. Line your 9×13-inch pan with parchment, leaving extra hanging over the sides so you can lift out the treats later.
03 -
Mix both sugars into your cooled chocolate mix. Add eggs one after another, mixing until smooth each time. Add the vanilla, then gently fold in salt, flour, and cocoa powder.
04 -
Pour your mix into the ready pan and bake for 35-36 minutes until the edges start pulling away. When you stick in a toothpick, it should come out with just a few wet crumbs. Let them cool completely in the pan on a wire rack.
05 -
Beat the butter until it's smooth and fluffy, around 2 minutes. Add powdered sugar and milk, beating slowly for 2 minutes, then crank it up high for 1 minute. Mix in peppermint extract and food coloring (if using) and beat on high for another minute.
06 -
Spread the mint frosting all over your cooled brownies. Stick them in the fridge for at least an hour to firm up before adding the chocolate top.
07 -
Melt butter and chocolate chips together in a pot over medium heat or in your microwave in 20-second bursts. Pour this over the hardened mint layer and smooth it out with a flat spatula.
08 -
Chill in the fridge for at least an hour until the chocolate hardens. Cut into squares with a sharp knife, wiping it clean between cuts for pretty edges.