Soak 8 bamboo skewers in cold water for several hours or overnight so that they do not burn during cooking.
Mix together the sherry, sesame oil, five-spice powder, ginger, sugar, garlic and soy sauce in a small lidded container or screw-top jar. Shake well to mix.
Put the pork in a polythene food bag and add the marinade. Turn to coat each piece, then transfer to the refrigerator to marinate for at least 2 hours or overnight.
Thread the pieces of pork, red pepper and onion alternately on to the skewers. Line the lower rack of the halogen oven with foil and arrange the skewers side by side on the foil.
Set the temperature to 200°C (392°F) and cook the kebabs for 18–20 minutes, turning once or twice, until the pork is cooked through. Serve the kebabs with steamed Thai fragrant rice, scattered with finely chopped spring onions.