FOR Food. Somerville, MA 1/5/2012 The upstairs dining area as well as a bar to the left. Casa B, a new tapas restaurant in Union Square is photographed in Somerville, MA on Thursday, January 5, 2012. (Yoon S. Byun/Globe Staff) Section: Food Slug: 13tippic Reporter: Devra First LOID: 5.0.716930911