These were some big ‘ole bok choy bunches. Bok choy is part of the cabbage family, formally called Brassicas. Brassicas include a huge number of vegetables (cauliflower, brussels sprouts, turnips, radishes etc.) but most of those fall under just two species, Brassica oleracea and Brassica rapa, and are just varieties of the species, like granny smith and red delicious are varieties of the same species; apple. Bok choy is part of the Brassica rapa group which also includes turnips, rapini, and napa cabbage.