Minced Pork and Watermelon Lettuce Wraps

Heat the vegetable oil in a heavy, non-stick skillet over high heat. Cook and stir the garlic, ginger, and onion in the hot oil until fragrant, about 1 minute; add the ground pork to the mixture and cook until completely browned, 7 to 10 minutes. Drain any excess liquid from the skillet. Reduce the heat to medium. Add the carrot and celery to the pork mixture; cook and stir until the carrot and celery begin to soften, 2 to 3 minutes. Stir the soy sauce and green onions into the mixture; remove the skillet from the heat and add the hoisin sauce and pine nuts. Stir the mixture until evenly mixed. Fold the watermelon into the mixture. Spoon the pork mixture into the middle of the lettuce leaves; wrap the lettuce around the filling to serve.