In a small bowl, whisk together marinade: soy sauce, rice vinegar, plum preserves, sesame oil, garlic, ginger, Chinese five spice powder and hot sauce. Pour marinade into a large re-sealable plastic bag and add pork tenderloin.
Seal bag, removing as much air as possible, and shake evenly to coat. Marinate in the refrigerator for 30 minutes or overnight.
Pre-heat the broiler on high and spray a broiler pan with non-stick spray. Place pork in the middle of the pan and broil for 7-8 minutes per side or until pork reaches internal cooking temperature of 165.
Remove pork from oven and cover loosely with foil while meat rests for 10 minutes. Slice and serve with steamed spinach drizzled with sesame oil. Garnish with toasted sesame seeds.