If you're not a fan of seafood, there's little point navigating to Hia Wan Khao Tom Pla whose signature is khao tom, soft boiled rice soup with fish.
It's an immediately impressive display of seafood laid out in ice-laden trays along the exterior of the shophouse. Meaty cuts of grouper and seabass, fresh oysters, large river prawns, delicate pomfret, fish eggs, jellyfish and piles of squid. Then there's the choice between typically plain khao tom soup simmered with white pepper and Thai celery, a better way to taste the flavour of the seafood, or the more punchy tom yum style that's slightly creamy and spiked with chillies, lemongrass and galangal.
It's typical of Bangkok's shophouses with little difference between outside and in, the tables creeping out from the open sided front onto the pavement and an outdoor kitchen station where the fish is quickly poached in the warm rice soup. There's little English here, but the outdoor display of seafood is a good place to point at what you'd like.
Hia Wan Khao Tom Pla has always been a busy little spot with Bangkokians, but has become even more so since Michelin awarded it a coveted Bib Gourmand. It opens from 4.30pm through to 11.30pm everyday other than public holidays, but it's best to avoid the dinner-time rush. Simple bowls of rice soup start from 60 THB (US $1.95), but expect to pay upwards of 120 THB (US $3.85) for a mix of seafood.