Line a 18cm x 28cm slice tin (or a 20cm square cake tin) with baking paper. Make sure the paper comes all the way up the sides so you can remove the Rocky Road easily once it has set.
Place the dried cranberries, halved macadamia nuts and marshmallows, pistachios and freeze-dried berries into a large bowl. Stir to distribute them.
Melt the white chocolate pieces: Place them into a microwave-proof bowl or jug. Heat, uncovered, on 40-50% power, stirring every 20-25 seconds, until there are only a few smallish pieces of chocolate left. Stir well as the residual heat will melt the remaining chocolate. Set aside to cool for 2-3 minutes otherwise if it is too hot it will melt the marshmallows. You can also melt the chocolate on the stovetop over low heat, either in a saucepan or double boiler.
Once the chocolate is cooled slightly, pour it over the ingredients in the bowl and using a large clean metal spoon (or spatula) stir everything together gently until well combined and everything is coated in chocolate.
Spoon the mixture into the prepared slice tin and spread out evenly, pressing down lightly as you go.
Optional: Decorate the top of the rocky road by sprinkling over some crushed pistachios and crushed freeze-dried berries or extra dried cranberries.
Place in the fridge for at least 1.5hrs or until completely set.
Cut into slices or squares. Use a sharp knife and run the blade under hot water, drying well, before each cut. This will make slicing easier and give cleaner edges. I also recommend removing the rocky road from the fridge for 5-10 minutes before slicing too.
Store the Rocky Road in the fridge in an airtight container. It will last for 2-3 weeks.