While you’re waiting for airfares and red tape to relax enough to make your own trip to Cuba, you can visit Gustazo, a cozy, attractive outpost of the island’s lusty cuisine, perched on Waltham’s town common. Expect exemplary renditions of the classics: a tremendous Cuban sandwich, the rich coconut-milk seafood stew that is mariscada, slow-roasted puerco asado, a delectable ropa vieja of shredded flank steak and a mouth-puckering swordfish ceviche. You’ll have to take the cigar outside.