In a heat-safe glass bowl set over a saucepan of simmering water, melt chocolate (do not let bowl touch water); whisk until smooth and shiny. Fold marshmallows and ½ cup candy into chocolate until evenly combined. Drop heaping spoonfuls of chocolate mixture onto 2 parchment-lined baking sheets; sprinkle with remaining candy. Allow to cool for several hrs. Store in a cool, dry place with parchment between layers of candy for up to 1 week. Serve at room temperature.