Lightly grease and line a 26 x 16cm slice pan with baking paper.
Place chocolate in a large microwave-safe bowl. Cook in 30 seconds bursts, stirring, until melted and smooth.
Stir in the biscuits, marshmallows, and cherries through, coating well with chocolate.
Pour into the prepared dish and refrigerate, until firm. Cut into large pieces. Store in an airtight container.
For a traditional option, replace the biscuits with roasted peanuts or any other nut. You can also melt chocolate in a heatproof bowl over simmering water - do not let water touch the base of the bowl.