I've come across some information recently about "Spirit Cooking", and it's not what most people think it is:

Summary of Spirit Cooking: https://www.moma.org/collection/works/143945 (https://archive.is/aRNMp))

Different recipes, many of which seem to be completely innocent (or at least non-Satanist): http://www.editionjs.com/img/abramovic/ (https://archive.is/O5rCj))

Also, they hypothesis goes that Marina Abramovic is a Satanic occult leader for very powerful elites that are getting guidance about pedophilia, human sacrifice, etc. I would expect someone that holds this many serious secrets to be extremely rich. Instead, she's worth a relatively modest $10M: http://www.celebritynetworth.com/richest-celebrities/actors/marina-abramovic-net-worth/ (https://archive.is/Ndb1c))

Marina Abramovic originally came of interest in a WikiLeaks Podesta email where she was mentioned and emailing about going to a private party for Spirit Cooking: https://wikileaks.org/podesta-emails/emailid/15893

Despite many people looking into her, there has not been any solid connection between her and #PizzaGate outside of this email.