Coat a platter or dish with butter. Put the first 5 ingredients in a medium sized mixing bowl. Mix the evaporated milk and sugar in a medium sized sauce pan and heat to a low boil, stirring constantly. Continue boiling and stirring for 6 minutes. Immediately pour the milk and sugar mixture over the chocolate chip mixture in the bowl and begin mixing. Mix well until all the marshmellows are completely melted. Pour the fudge on to the buttered platter and refrigerate until firm. Lick that spoon! Yum..... After the candy hardens, cut into cubes and serve. Store in the refrigerator.