Seared Scallops with Grapefruit Sauce

Remove skin and white pith from grapefruit using a sharp knife and discard. Hold the fruit over a bowl and cut between the membrane to release individual sections into the bowl, collecting the juice as well. Squeeze any remaining juice from the membranes into the bowl. Discard the seeds and membranes. Drain the juice into a measuring cup and add water, if necessary, to make 1/4 cup. Sprinkle both sides of scallops with salt and pepper. Heat 2 teaspoons oil in a medium nonstick skillet over medium-high heat. Add the scallops and cook until golden, 3 to 4 minutes per side. Transfer the scallops to a plate and cover with foil to keep warm. Add the remaining 1 teaspoon oil to the pan. Add shallot and cook, stirring often, until softened, about 1 minute. Add the reserved grapefruit juice and vermouth (or wine) and bring to a boil. Boil until reduced by half, about 3 minutes. Reduce heat to low and add honey, the grapefruit sections and mint. Return the scallops to the pan and reheat gently, turning to coat with the sauce.