Soak fish maw until tender then remove and cut into bite-sized pieces. Put fish maw into a basin of water and add vinegar. Give it a stir. Remove and rinse under clear water. Squeeze out excess water and leave to strain in a colander. Next blanch fish maw in a saucepan of boiling water for 2-3 minutes. Dish out and strain off excess water.
Heat sesame oil and fry ginger slices until fragrant. Splash in Shao Hsing Hua Tiau wine and pour in chicken stock. Bring to a quick simmering boil.
Add seasoning, fish maw and chicken. Cook to a boil. Add crab meat followed by thickening. Stir in beaten egg and add an extra dash of sesame oil.