In a large bowl, combine the ground pork, vinegar, soy sauce, brown sugar, water, garlic powder, onion powder, black pepper, and red pepper flakes.
Mix well to combine.
Cover the bowl and refrigerate for at least 8 hours, or overnight.
Preheat a grill or grill pan to medium heat.
Form the pork mixture into patties about 1 inch thick.
Grill the patties for 5-7 minutes per side, or until cooked through.
Serve immediately.
Serve immediately with rice.