While the meat is chilling, combine the grated pear, soy sauce, sesame oil, ginger, red pepper flakes and sugar in a large zip-top plastic bag.
After 30 minutes of chilling, use a sharp knife to slice the meat into very thin strips. Add the meat to the marinade and mix everything together until evenly coated. Let sit at room temperature for at least 1 hour, or chill in the refrigerator for up to 8 hours.
Heat 1 tablespoon vegetable oil in a large skillet or cast iron or wok over medium-high. Remove half of meat from marinade, letting excess drip back into bag. Season lightly with salt and cook in a single layer without moving until lightly browned, about 1-2 minutes to create a golden sear. Toss meat and continue to cook, tossing occasionally, until cooked through and crisp at edges, about 3-4 minutes total. Transfer to a plate. Repeat with remaining 1 tablespoon vegetable oil, remaining meat, and more salt. Discard excess marinade.
To make the scallion salad, combine the scallions, cilantro, sesame oil, rice vinegar and sesame seeds in a medium bowl. Toss to combine. Season with salt as needed.
Serve the the cooked meat with lettuce cups, steamed white rice and the scallion salad. Assemble lettuce wraps as needed.