Preheat you oven to 350 degrees
Spray or butter a 12 inch cast iron skillet
Melt the butter in the microwave, and add the sugar, then the eggs, then the vanilla. Mix until well combined
Add the cocoa powder, milk powder, and espresso powder and mix until well blended. Scrape the sides and mix until all is blended.
Finally add in the flour, salt and baking powder, mix only until just combined, about 15-20 seconds.
Do NOT over mix... the brownies will be tough.
Add the Andes mints and mix until just mixed in about 15 seconds.
Pour the brownies into the skillet and press down until they are evenly spread.
Place into your pre-heated oven and bake for between 23 to 27 minutes.
Take the brownies out of the oven and serve with your favorite ice cream... vanilla or mint chip are amazing on this.
Enjoy!