Melt chocolate chips, nuts and peanut butter together. Place half in the bottom of a 9x13 buttered pan and cool until it no longer looks shiny. Microwave marshmallows in a large bowl and add frosting and blend well. Spread over set chocolate mixture and let set until firm. Spread the final layer of chocolate over the top and let cool again. Cut into pieces and store in refrigerator.
***You may want to increase the marshmallows a bit to make a firmer center 1/2 C mini or 5 large. A popular baking manufacturer in the US still makes the Cherry Frosting, but not all grocery stores carry it.