This Trinidadian mixture puts the heat of the Caribbean into egg nog. It is very popular around Christmas and New Year in Trinidad and many people have recipes. They are all similar in combining eggs cream and rum.
To Make 1 rum bottle full of Punch
1 pint of dark rum
1 tin of condensed milk
1 cup of thick cream
1/2 cup milk
(in Trinidad they use evaporated milk, in the USA half and half would work)
A good teaspoon and a half of fresh ground nutmeg
The zest of a lemon or lime
tspn Angostura Bitter (if you don't have this don't worry)
Blend until thoroughly mixed and bottle for a day or two before drinking.
This is the basic recipe, I have speculated that heating slowly in a bain marie until the eggs thicken might help the consistency but be careful not to overcook. Most people make two bottles at a time as that uses up one whole bottle of rum and provides a spare bottle to fill. The rum quality is not that important, people will tell you only use Trinidad rum but a good dark demerara such as Navy rum is fine.