Cake tin: line a square slice or cake tin with greaseproof paper (Tray dimensions 24cm x 5cm, 9 inch x 2 inches). Leave an overhang on the sides.
Rocky road filling: combine, maltesers, mini marshmallows, peanuts, and chopped raspberries in a large mixing bowl. Stir till consistently combined.
Chocolate: add chocolate melts to a large heatproof jug. Place in microwave and heat on high for 2 mins. Remove and stir to melt the rest of the chocolate.
Combine: pour melted chocolate over combined rocky road ingredients, stir till they are covered in chocolate.
Into tin: transfer wet rocky road mix to lined slice tray, then place in refrigerator to set.
Refrigerate: after a (minimum of 1 hour) remove rocky road from fridge and set on bench for 10 mins.
Portion: pull Malteser rocky road from tin, by grabbing parchment paper on either side and lifting rocky road up and out of tin. Use a sharp knife to cut into pieces.
To store: store the rocky road in the fridge in a sealed, airtight container for up to 3 weeks.