This is a mild curried dish, usually served as a counterpoint to a more intense curry or garlic dish. It can be prepared with crab claws, or with a cup of crab meat, or a mixture of crab meat and shrimp. Since it is often eaten with chop sticks, you might consider removing the meat from the claws, as this makes it easier for the spice flavours to penetrate and easier to eat the food. Thai curry powder (phom kari) is unlikely to be available outside Thailand. Use a mild Indian curry powder instead. Prik yuak is a sweet green chili, if not available use green bell peppers or canned jalapeños to taste.