Rocky road

1.Line base and sides of a 20cm square pan with baking paper. In a large heatproof bowl, melt chocolate over a saucepan of simmering water. Remove from heat and add biscuit chunks and marshmallows. Stir to coat and spoon into prepared pan. Refrigerate for 2 hours, until set.

2.Cut into squares and store in an airtight container in fridge until ready to serve.