This may have passed you by but round these parts at this time of year there is a quaint celebration called Christmas - the origins are lost in the mists of time, but it is believed to originate from a tribe of credit based shoppers.
Anyway this drink is based on a traditional yuletide drink known as Eggnog, but lifted and lightened a little.
The Eggnog is actually only part finished prior to the addition of brandy and cream, specifically after step 5 of method 1 in these instructions.
2 shots cognac
1 shot part finished eggnog
3/4 shot lemon juice
1/2 egg white
Shake super hard over ice and double strain into a coupe. Dust elegantly with cinnamon.