Place sauce ingredients in a small pot and bring to a boil over medium-high heat. Reduce heat until sauce gentle simmers. Cook the sauce until it lightly thickens, about 10-15 minutes, and then reserve over low heat. Heat a stovetop or electric non-stick grill to medium-high heat. Toss scallops with oil, salt, pepper and lime juice. Grill 1-2 minutes per side, or until just cooked through. Pour a pool of sauce on 4 plates or scallop shells. Divide and arrange scallops over top, sprinkle with cilantro, if desired, and serve.