At just seven months old, the Philadelphia Mobile Food Association (PMFA) is by all accounts a baby, but the soon-to-be-incorporated collective, made up of more than 50 entrepreneurial street-eats minds, has made some hot-‘n’-fresh headway in recent months. Following a small but successful June 2012 pop-up at the Lutheran Settlement House in Fishtown, the PMFA threw a fully realized food bash, the Brewerytown Food Truck Roundup, on Friday.