Heat the butter in a pan, add the onion and cook for about 5 minutes until softened. Stir in the mince, breadcrumbs, Worcestershire sauce and egg and season well. Cool.

Use damp hands to shape the mixture into twelve balls and chill for 20 minutes. Heat the oil in a large frying pan and brown the meatballs well. Remove with a slotted spoon and set aside.

Add the peppers to the pan and fry gently for 2 minutes. Stir in the sugar, soy sauce, vinegar, orange juice, stock and seasoning. Bring to the boil and return the meatballs to the pan.

Cover and cook in the oven at 180°C (350°F) mark 4 for about 45 minutes. Skim if necessary. Drain the cooking liquid from the meatballs and keep them warm in a serving dish.

Mix the cornflour to a smooth paste with a little water. Stir into the pan juices and bring to the boil. Cook stirring for 2-3 minutes and pour over the meatballs.