Cut the chicken meat into slices and place them in a bowl.
Add a pinch salt, sugar, Ve-Tsin ,1/2 teaspoon sherry, few drops sesame oil, 1/2 teaspoon soy sauce and a pinch cornflour and work all thoroughly together.
Leave to rest.
Chop the ginger and garlic.
Add the black beans and mash together to a smooth paste.
Heat 1 dessertspoon of peanut oil in frying-pan and cook the onion in it for 1-2 minutes.
Add the above paste and cook for a further minute.
Meanwhile, have deep peanut oil heating to 375°F. or 190°C.
Drop the chicken pieces into it and cook them till a warm gold colour.
Drain them and add them to the frying-pan.
Add also another pinch salt, sugar, Ve-Tsin, the remaining sherry, few drops sesame oil, remaining soy sauce and the stock.
Bring to the boil.
Finally, blend 1 level teaspoon cornflour with the water, stir it in and boil for 1 1/2 minutes.