To make the gravy: Heat two to three tablespoons oil, saute lemon grass, galangal and combined spice ingredients until fragrant. Add in crab and water and bring to a boil. Lower the heat and simmer gravy for 10 minutes.
Add cockles and coconut milk. Continue to simmer for another 10 minutes. Remove gravy from the heat or reduce the heat to very low so that gravy is warm when ready to serve.
To serve: Divide mee into individual bowls or deep sauce plates. Top with bean sprouts, fish cake, fish balls, squid balls and prawns.