Add the chocolate chips and butter to a small pot and heat it on the stove over medium low heat. Stir frequently until they're both totally melted. 2 cups semi sweet chocolate chips, 1/2 cup unsalted butter
Set the chocolate aside and let it cool for about 10 minutes.
Add the marshmallows and walnuts to a large bowl, and stir them together. 10 oz colorful mini marshmallows, 1 cup walnuts
Pour the cooled chocolate over the marshmallows, and mix to stir until they are evenly coated. Set aside for a couple minutes.
Spread out two long pieces of plastic wrap on a flat surface. Sprinkle each with most of the coconut, divided evenly between them. 1 cup sweetened shredded coconut
Scoop the chocolate mixture in a long log shape on top of the coconut. Sprinkle the remaining coconut on top of the chocolate.
Roll the mixture up into a log using the plastic wrap. Squish and move the chocolate around to get the log as tight as you can. Roll it up and twist the ends to seal the plastic. Tape the plastic wrap closed if needed.
Place in the fridge to chill for at least 2 hours, up to 7 days. Slice with a serrated knife into 1/2 inch pieces.