Made by the Once Again Nut Butter company, mystery butter consists of the end of day runs of nut butters mixed together. Thus, it will contain varying amounts of peanut, cashew, sesame seed, almond, and other nut butters. The trick is that they sell it at a heavy discount since it's stuff they would otherwise be disposing of, and the consumer has no guarantee of consistency. Sometimes it's just peanut butter, sometimes you can taste every kind of nut butter in it. So it's for people who like living life on the edge--you know, skydivers, cigarette smokers, people like that.