First, pat dry the pork belly with kitchen paper and cut into small cubes.
Wash and dice the zucchini.
Peel the onion and dice small.
Peel and finely chop the ginger.
Heat a skillet without adding any oil and sear the pork belly turning frequently for 5 minutes.
Add the zucchini and onion cubes and the ginger to the meat.
Mix everything well and fry for another 5-7 minutes.
Push the contents to the side of the pan, adding oil to the middle.
Stir the black bean paste together with the oyster sauce into the oil and sauté for about 1 minute.
Mix all the ingredients in the pan well.
Add the water and then cover and simmer on a low flame for about 8 minutes.
Mix the cornstarch with a little sugar until smooth and mix into the black bean sauce, stirring constantly.