It is often made by sautéing or broiling liver and onions, adding hard-boiled eggs, salt and pepper, and grinding that mixture. The quintessential fat used is schmaltz, but different methods and materials exist, and the exact process and ingredients may vary from chef to chef.
Chopped liver is high in protein but also high in fat and cholesterol. Thus, low fat, mock, and vegetarian versions of chopped liver exist that are frequently made of a combination or base of peas, string beans, eggplant, or mushrooms. One Parve variation is the Israeli eggplant salad.
Chopped liver as an expression
Since eating chopped liver may not be appreciated by everyone, the Jewish English expression "What am I, chopped liver?", signifies frustration or anger at being ignored on a social level.
An alternative explanation for the etymology of the "What am I, chopped liver?" expression is that chopped liver was traditionally served as a side dish rather than a main course. The phrase, therefore may have originally meant to express a feeling of being overlooked, as a "side dish."
The etymology of the idiom is difficult to trace, with much of spoken references in older television, comedy and cinema unavailable in text form, but one early occurrence appears in the book titled, The Curtain Never Falls, by comedian Joey Adams, published in 1949.
- Vegetarian Chopped Liver (Pareve) http://kosherfood.about.com/od/vegetarianmaindishes/r/vegie_chopliver.htm
- Ask the Rabbi: What Am I, Chopped Liver? at Ohr Somayach
- The Curtain Never Falls page reference at Google Books
- Media related to Chopped liver at Wikimedia Commons