Make sauce. Grate the apple, ginger and onion. Add soy sauce, sake and water.
Spread out the pork loin and marinate in the sauce. Rest for 10-15 minutes. While waiting, shred the cabbage into thin strips.
Separate the meat and the marinade.
Heat the oil in a pan and spread the pork out to fry. Sprinkle flour on the pork (optional).
When the pork is almost cooked, add marinade and thicken it.
Serve on a plate with shredded cabbage.