You'll start by making the mousse. Whip the whipped cream and milk together in a large bowl (or your stand mixer’s bowl) until completely combined.
Sprinkle the instant chocolate pudding mix (it must be instant or this recipe won’t work) over the whipped topping mixture. Beat on low for 30 seconds then on high speed for 2 minutes, scraping the sides of the bowl often to make sure everything’s evenly incorporated.
Once you finish beating the mousse, cover the bowl with plastic wrap and place in the fridge until you’re finished making the reindeer.
To assemble the reindeer, you will need to gather all of your components. Melt ¼ cup of chocolate chips to be used as ‘glue’ (it makes no difference whether you use white, semi-sweet or milk chocolate chips). Just melt them in the microwave for approximately 20 seconds and use a toothpick to apply the chocolate glue where needed.
Choose where you would like to locate the eyes on the cup, apply a small amount of melted chocolate to the backs of the eyes then adhere them to the correct spot. Hold them in place for just a second until the chocolate sets then repeat for the nose (if you’re using a candy with a logo stamped on one side, just apply the melted chocolate over the logo so that the blank side is facing out). Allow the melted chocolate to set while you make the rest of the reindeer.
After the reindeer have been made, place about a cup and a half of chocolate mousse into a zip top sandwich bag. Seal the bag, snip one corner and use the bag to pipe the mousse into the cups. Then place the candy canes inside the cup as ‘antlers’. They will displace a certain amount of mousse so make sure to fill the cups to the top or slightly below. You can always add more mousse after you put the antlers in place if needed.
If you're not serving these little guys immediately, place them in the fridge without antlers until ready to serve. The candy canes will begin to melt into the mousse after a while, so keep them separate until just ready to serve.