What did pierce egan add to eggnog recipe for ben and jerry?

Unfortunately, there's no public information available about a specific recipe Pierce Egan created for Ben & Jerry's.

Ben & Jerry's does not have a "Eggnog" flavor, and their recipe development process isn't typically shared with the public. Additionally, "Pierce Egan" isn't a commonly known figure in the ice cream or food industry, making it difficult to find any connections to Ben & Jerry's.

It's possible that the information you're looking for might be:

* Misremembered: Perhaps the name or detail about the ingredient is slightly different.

* Specific to a particular location: Ben & Jerry's has various seasonal and regional flavors that might be less widely known.

* Not publicly available: The recipe might be confidential and only known to those involved in its development.

If you have any other details, like the year you heard about this recipe or the specific location, it could help narrow down the search!