In a large bowl whisk together egg yolks and sugar until the the mixture becomes a light and pale yellow.
Pour the milk, nutmeg, and cinnamon into a medium saucepan, and place over medium heat. Gently increase the temperature of the liquid until the sides of the milk start to lightly bubble and steam. Do not bring to a boil!
Once milk is heated to a gentle simmer, pour ¼ cup of the hot milk into the sugar and egg mixture while stirring constantly. Slowly pour more of the milk mixture into the egg and sugar mixture. Don’t rush this process as if you go too quickly you will cook the eggs too fast.
Once you have added all of the milk mixture into the eggs and sugar, pour the mixture back into the pot and place over medium low heat. Constantly stir with a wooden spoon, until the mixture begins to thicken slightly, and coats the back of the spoon. It helps to have a candy thermometer, but not necessary; if you have one, cook until the mixture reaches 160°F. Do not allow the mixture to boil, or it will curdle. (If the mixture does curdle you may be able to save it by running it through a blender.)
Once mixture is coating the back of the spoon, remove from heat and stir in the 1 cup of heavy cream. Now allow the mixture to cool for about an hour.
After the mixture has cooled add in the vanilla extract, and rum or bourbon if you are in the mood.
Serve with a cinnamon stick and holiday vibes! Enjoy!
