Prepare brownie mix according to manufacturer instructions. Prepare a half sheet tray with an extender collar. Deposit 3 pounds filling into the half sheet, bake until set and cool completely. Place 1 pint heavy cream in a pan and bring to a boil, pour hot cream over 2 pounds ruby chocolate. Mix until chocolate is completely melted, mix in some food coloring if needed. Mix in 1 pound salted whole roasted peanuts and 12 ounces mini marshmallows. Spread prepared mixture over cooled brownies, place in cooler overnight. The next day, unmold and cut to desired size.
If ruby chocolate is unavailable in your area, you can substitute using a combination of white and dark chocolates with the Chefmaster Princess Pink food coloring. For the ganache, substitute 25.6 ounces white chocolate and 6.4 ounces dark chocolate for the ruby chocolate and follow the directions above being sure to use a good amount of the food coloring.