I first heard about this recipe on an NPR program. The comments and recipe below were copied, in 2013, from a website whose name and URL I have long forgotten. I have made this many times over the years and always enjoyed the results.

As I recall from the NPR program, at some point Dr. Lancefield and her colleagues wondered about the science behind making this with a dozen raw eggs and nobody ever becoming sick from it. So they did an experiment. They made a batch and injected a massive dose of salmonella into it. It then sat in the fridge and was tested each week. After a short time–two or three weeks if memory serves–there was no trace of salmonella. The alcohol did what you might expect. If there is a lesson from this, I would say: Don’t skimp on the alcohol and Do make it by Thanksgiving to be consumed at Christmas.

With that said, the following is the recipe as I copied it down.

Dr. Rebecca Lancefield’s Eggnog

This recipe comes from Dr. Rebecca Lancefield (1895 – 1981), a prominent microbiologist who worked at The Rockefeller University. One of her perhaps lesser-known legacies is related to eggnog: every year, she would make eggnog in the lab before Thanksgiving, let it “mellow,” and then serve it at Christmas. Forty years later, the eggnog tradition persists in that laboratory.

Ingredients

12 Eggs
1 Pint Bourbon or Tennessee Sour Mash Whiskey
1 Quart Rum
1 Quart Heavy Cream
1 Quart Light Cream
1/2 – 3/4 Lb Sugar (to taste)
Nutmeg

Directions

Beat the eggs, add bourbon and rum slowly while stirring to prevent precipitation of egg proteins.
Beat heavy cream separately until it peaks and add it to the egg/bourbon/rum mix.
Add the light cream while stirring.
Add the sugar to taste while stirring. Add nutmeg to taste.
Leave standing at least overnight in refrigerator with the lid slightly ajar.
Serve after at least 2 – 3 weeks in the refrigerator.