Grease and line the base and sides of a 29cm x 16cm rectangular tin with baking paper.
Cut marshmallows into quarters using scissors. In a large bowl, place marshmallows, coconut, pistachios, popcorn, dried apricots, cranberries and goji berries. Mix well.
In a heatproof bowl, melt chocolate on high power in the microwave for 1 minute, or until melted and smooth. Stir chocolate halfway through cooking to prevent burning.
Pour chocolate over marshmallow mixture, quickly stir, then pour mixture into prepared tin. Spread mixture over base with a spatula. Refrigerate for 15-20 minutes, or until set. Cut into squares or break into pieces to serve.