Combine marshmallow cream and melted chocolate chips in a mixing bowl.
Gently fold until thoroughly incorporated.
Let stand, uncovered, for 15 minutes.
With your hands, form mixture into bars of desired size and place on cookie sheet lined with wax paper.
(If mixture is too sticky to handle, it needs more melted chocolate.) Melt dipping chocolate or remaining chocolate chips in microwave for about 2 minutes, stirring every thirty seconds to prevent scorching.
Dip bars into melted chocolate, and place back on cookie sheet.
Put in freezer for about 10 minutes, or until chocolate sets.
Variation: for Snickers bars, soften some caramels and flatten onto on bars before dipping in chocolate.
Press peanuts into caramel, then harden bars in freezer for 5 minutes.
Dip in chocolate according to the above instructions.