Place the caramelized onion in a food processor. Add the sardines with about a tablespoon of the oil from the can. Grind in some pepper. Whirl until a paste forms. Taste and add more pepper and sardine oil if necessary.
Recipe by Empowered Sustenance at https://empoweredsustenance.com/caramelized-onion-sardine-pate-paleo-gaps/