At first glance, the Kennedy Biscuit Lofts are simply a group of apartment buildings with a pleasant courtyard, off a quiet street near Cambridge’s Central Square. But a series of plaques in the brick reveal this location to be the former home of the F.A. Kennedy Steam Bakery, where the Fig Newton—named after the nearby town of Newton—was first conceived and produced in 1891. Built in 1875, the bakery was later bought by Nabisco (who continue to sell Fig Newtons to this day). The factory eventually closed, but was later…