- Heat the olive oil in a large saucepan and brown the meat in it. It will produce a lot of moisture but persevere until it has all evaporated and the meat starts to turn golden.
- Slowly pour the vinegar over it and, when the steam subsides, add the wine.
- Then add all the remaining ingredients except the vegetable oil, onions and Sugar, cover and cook slowly for 1 hour or until the meat is almost tender.
- Heat the vegetable oil in a frying pan and add as many onions in one layer as it will take. Sautee them gently for about 15 minutes, shaking and turning them over until they brown lightly.
- Lift them out with a slotted spoon and spread them over the meat, distributing them evenly. Repeat until all the onions are done.
- Sprinkle the Sugar over the onions, cover and cook very gently for 30 minutes, until the onions are soft but not disintegrating.
- Do not stir once the onions have been added, but rotate the saucepan occasionally to coat them in the sauce.