Place the cream, vanilla extract and caster sugar into a clean and dry Thermomix bowl. Whip on Speed 3.5 until soft peaks form (this will take quite a while due to the volume of cream - I recommend doing this in 2 batches).
Spread some of the whipped cream in a large circle along the outside edge of your serving plate.
Hold one chocolate ripple biscuit in your hand. Spread a teaspoon of whipped cream onto the flat edge and place another chocolate ripple biscuit on top.
Repeat until you have a stack of 3 biscuits in your hand. Stand the stack upright onto the cream on the serving plate.
Repeat with another 3 biscuits and then join that stack to the serving platter to begin to form one circular 'wreath'. Repeat until all of the biscuits have been used.
Use the remaining whipped cream to spread over the entire outside of the wreath (you may have some leftover).
Decorate by drizzling caramel sauce and Nutella (see note) over the top of the wreath.
Add the Malteser reindeers (pressing in firmly enough to stay put!).
Sprinkle over the edible silver balls. For best results, place in the fridge overnight to allow the biscuits to soften.