Cambridge Carnival this Sunday (also Haverhill Latino Festival and Sat Boston Carnival)
Is from 12-7 in Kendall Sq, I believe with installations both at Tech Square and One Broadway. Some of the chow can sell out, so if you arrive earlier there is more selection.
I belive the Boston Carnival is on Saturday, I believe in Franklin Park and has similar offerings.
The North End has St Anthony's Feast this weekend.
And Haverhill has a Latino Festival at GAR Park, not certain about chow.
East Cambridge feast coming soon as well as Brazilian Independence Day Festival.