Grease and line a dish with cling wrap.
In a small bowl, place the cold water and sprinkle the gelatine over it. Leave for 10 minutes.

Heat the caster sugar, glucose syrup and 100 ml of water in a pot until the sugar has melted. Bring to the boil for 3-5 minutes until the thermometer reaches 120C.

In a water bath, heat the glucose syrup on a medium to high heat until it becomes a clear liquid. Pour into the caster sugar mixture and add the vanilla essence and ginger. Mix until combined.

Whip the egg whites until firm. Slowly add the sugar syrup while whipping and continue to whip for 10 aunties until the mixture becomes silky and starts to crawl up the beaters.

Divide into 3 bowls and add food colouring to each. Stir to combine. In your lined dish, place blobs of the colours until all the mixture is in the dish. Using something thats long and thin, do squiggles through the mixture to slightly combine the colours. Place int he fridge for at least 1 hour to set.

Sift the icing sugar and cornflour together. Cut the marshmallow up into desired sized chunks and roll in the mixture. Store in an airtight container and consume within a few days (if it lasts that long!)