Corned Beef Guisao (Guisado de Corned Beef)

1/2 pound fish1 tbsp. cornstarch2 tbsp. sboyu1 tbsp. black beans (dau see)1 tsp. sugar1/2 tsp. salt1 tbsp. Chung Choi1 tsp. oil1 piece ginger crushed and cut fine1 clove garlic2 sprigs green onions, cut fine Clean fish and let dry. Chop chung choi fine; mash black beans. Mix well ginger, starch, sugar, salt, chung choi, dau…