It'd be naive to dismiss the class politics involved in championing Cantonese cuisine above all others. If ingredients can make or break a meal, than there's surely an advantage in being able to afford high end, exotic ingredients. Instead of being the best, Cantonese cuisine might simply be the most enviable, depending on one's subjective taste.
Sea cucumber is one moderately affordable (and, unfortunately, overharvested) example. The echinoderm can fetch north of USD$110 a kilogram, prized for its purported health benefits, and the subject of the first part of Satie's Embryons desséchés. It's an acquired taste of nothing, notable for its spongy blandness. For that reason, it's often used in braises and soups that impart its flavor: at Red Star, it's braised with Chinese mushrooms, the sea cucumber soaking up its earthy richness.