Wash chicken gizzard thoroughly. Remove the yellowish skin on the gizzard if you bought it from the wet market.
Then rub the gizzard with rock salt to remove the mucus and odor of the gizzard.
Place the gizzard in medium size pan and add enough water to cover.
Add in the crushed garlic, ginger slices, bring to a boil and simmer for 30 minutes or until tender.
When done discard water and keep aside gizzard to cool down.
Slice the tender gizzard into bite size, keep aside.
In a wok heat generous amount of cooking oil until it start to smoke.
Saute the garlic, ginger strips, star anise for about a minute, add in the onion and continue to stir fry for another minute.
Add in the chicken gizzard and stir cook for st least 5 minutes.
Stir in the oyster sauce, soy sauce and 1/2 cup of water bring to a boil and simmer for 10 to 15 minutes stirring occasionally until the liquid turns to a thick oily sauce and almost dry.
Season with the ground black pepper, add the sliced chili and cook for another minute.