How to Make It
In a large, shallow dish, combine 1/2 cup of the pineapple juice and the grated ginger. Add the pork and turn to coat. Let stand at room temperature for 2 hours, turning often.
Meanwhile, in a small saucepan, combine the remaining 1 1/2 cups of pineapple juice with the chopped ginger and boil over high heat until reduced to 1/2 cup, about 20 minutes; strain the juice.
Light a grill. Remove the pork from the marinade. Drizzle the pork and scallions with oil and season with salt and pepper. Grill the pork over high heat until nicely charred, about 3 minutes. Turn and grill for 2 minutes longer. Brush the chops with the reduced pineapple juice and grill, turning and brushing constantly, until richly glazed, about 1 minute. Transfer the pork to a platter. Grill the scallions, turning a few times, until wilted and charred in spots, about 2 minutes. Serve the pork chops with the scallions.