Sometimes crossing over the Chao Phraya River to the western side of Bangkok is necessary. Visiting Ruam Tai, a small joint specialising in Southern Thai specialties, is one of those times. Good Southern food in Bangkok is few and far between.

There's a decent spread at Ruam Tai, far more than could be possibly tried in one lunch. Be warned, much of the Southern food is very spicy. The fried mackerel with a shrimp and chilli paste is always a good idea. As is the goong pad sataw, a stir fry with prawns and stink beans and, if they have them, cha om kai, crispy Thai omelettes with acacia leaves.

Most things available on the day are filled in trays displayed in the glass cabinet canteen-style along one edge of the small eatery. Expect at least 20-25 different things on offer. The rest of the space is just big enough for a single row of small wooden tables. It's a basic, utilitarian space - tile-clad walls, a few ceiling fans that do little to quench Bangkok's ferocious heat and the ever ubiquitous strip lighting. But it's comfortable enough for lunch or early dinner.

Most things are priced differently, but most plates around 40-50 THB (around US $1.25-1.50). Three of four dishes are a very good lunch for two. There's no translated menus here, nor do the friendly staff speak much English, but take a walk along the parade of Southern fare and point to what looks good.