1.Place live crabs in freezer for at least 2 hours, this is the most humane way to kill a crab. Slide a sharp, strong knife under top of shell at back of each crab, lever off shell and discard.
2.Remove and discard gills, wash crabs thoroughly. Using cleaver, chop body into quarters. Remove claws and nippers; chop nippers into large pieces.
3.Rinse beans well under cold running water, drain. Lightly mash beans. Heat oil in wok, stir-fry garlic, ginger and sambal until fragrant. Add beans, sauce, sugar, wine and stock, bring to a boil.
4.Add all of the crab, cook, covered, about 15 minutes or until crab changes colour. Place crab on serving plate, pour over sauce. Top with onion.
Place the green onion strips in iced water for about 20 minutes to make onion curls, a classic Chinese garnish.Note