Preheat oven to 200 C / 400 F. Line a baking tray with baking paper.
To make the marinade, combine together tomato ketchup (tomato sauce), honey, soy sauce, rice vinegar, brown sugar, and five spice powder in a small bowl. Season with salt and pepper. Set aside. Reserve ¼ cup of the marinade.
Place the rib rack on the baking tray.
Brush both sides of the ribs with the marinade.
Transfer to the oven. Bake for about 1 hour or until cooked through. Ideally, the meat needs to be very tender and read at least 71 C / 160 F on a meat thermometer.
While the ribs are in the oven, cook the sauce.
To make the sauce, place reserved marinade and beef broth (stock) in a saucepan over medium-high heat. Cook for about 5 minutes.
Garnish ribs with chopped spring onions (scallions).