Heat the double cream in a pan until it just starts to boil and then turn off the heat
Mix in both the milk and dark chocolate and then the unsalted butter until it is fully combined
Chop the Oreo's up into very small pieces, it doesn't have to be perfect but too big pieces might make it hard to shape the truffles
Mix the Oreo's into the chocolate/cream mixture and pour it all into a container and leave in the fridge for at least 3-4 hours, or preferably overnight
Using a cup of hot water, shape the truffles using a melon baller or two spoons to create small rounds - I dip my melon baller into the hot water each time to clean off any excess and make it easier for the mixture to drop out
Place back in the fridge for a couple more hours or a quick blast in the freezer so the mixture is very cold again to prevent the truffles melting when decorating
Melt the chocolate for decoration and dip each truffle into it trying to keep the coating light so that not much drips off and rest on a piece of greaseproof paper
Drizzle on the white chocolate and leave to set
Often if my truffles are misshapen I roll them in my hands so that it becomes smoother and hopefully rounder!
I use a dipping tool to help me with the decorating of the truffles, but you could also stick each truffle into a cocktail stick and stand them up in some polystyrene so the excess drips off itself!