The first text message came through on a Friday. "New Thai restaurant at Haymarket – Porkfat – awesome coral trout." It was from a pal who eats fiery southern Thai soups like the rest of us drink milk and might have a Master's in moo prik appreciation.

The next day, an email from a former colleague: "You need to visit Porkfat. Order the jowl."

On the third day, an Instagram post from Dan Hong (executive chef of Mr Wong) declaring the family-run 30-seater to be a "contender for possibly the best Thai food in Sydney". Bloody hell, all right then. Better check it out.

You can find Porkfat in the borderland between Chinatown and Ultimo. If you're after an endless selection of pulsing curries and forehead-mopping salads, the excellent southern-Thai-focused Caysorn is nearby. In contrast, Porkfat serves just 10 regular dishes, four specials and one $14 dessert.

That dessert – coconut ice-cream with bronzed peanuts, candied pumpkin and chewy palm seeds, which taste like a lychee that would prefer to be a jelly bean – is one of the few things that doesn't contain pork or its rendered fat.

I know you're wondering about that fantastic name, and oh boy, does it deliver!

You can mine the vermicelli for gems of crisp-fried fat, and I don't think I've been more satisfied all year.

Owner-chef Narin "Jack" Kulasai grew up in Central Thailand, and uses pork fat where other kitchens use commercial cooking oil. It creates a delicious foundation on which to layer clean, fresh flavours, while snow-white coral trout steamed with pork fat possesses rave-worthy roundness and complexity. Served in a broth invigorated by ginger and pickled plums, it's a steal for $55.

Meanwhile, pork skewers ($5), charred and slick with dark soy, bring the flavour of Bangkok's streets indoors. Grilled pork jowl ($27) is marinated in two-year-old fish sauce so it's blissfully rich and juicy, ready to be rolled in big leaves of mint and dipped in smoky nam jim with roasted rice.

For a dose of greens, there are sator beans stir-fried with pork fat, prawns and deeply spiced southern-style curry paste ($36).

The modest, spotless dining room is only half-full on the Saturday evening we visit, arriving late due to another rain-related train delay. Infectiously happy staff seat us on a mezzanine while folksy Thai music strums in the background. It's a welcoming place, though I wish I knew the wine list would only be four bottles long: BYO is encouraged.

Chardonnay would be the trick with toasty fried rice ($25), all garlic and crunch spangled with blue swimmer crab. However, som tum salad ($19) needs cold beer after beer to counter the chilli-packing papaya tangled with salted duck egg.

It's not the hottest thing, either: the real sinus-opener is a mango salad, topping lightly battered barramundi that's loaded with lemongrass and sprightly coriander ($28).

Another food-writer mate rocks up at one point, clutching at least four rieslings. (Clearly he's been here before.) "Did you order the vermicelli with baked prawns?"

he asks. Er, no, I tell him: there are only two of us and we're already stuffed. "You need to order the vermicelli. It's the signature." Bloody hell, all right then. Better come back.

I was always going to come back, though. This is thrilling, rewarding food. It's not surprising to learn Kulasai spent the past few years as a head chef at Long Chim Sydney, the CBD eatery founded by Thai-cooking high priest David Thompson. It's been a good year for Long Chim alumni with Annita Potter, Thompson's former right-hand woman, opening Woolloomooloo's Viand in February with a $145 tasting menu of uncompromising flavour and clarity.

You can't talk about "best Thai in Sydney" without bringing Viand into the discussion, but then – oh my! – Kulasai's vermicelli tiger prawns ($28). Taking their inspiration from a meal he used to eat after shifts at Nahm (Thompson's lauded Bangkok restaurant), garlic- and ginger-marinated noodles are sizzled in pork fat with oyster sauce and muscular prawns before being baked quickly in the oven. You can mine the vermicelli for gems of crisp-fried fat, and I don't think I've been more satisfied all year.

Is it the best Thai restaurant in Sydney? Quite possibly. But then so also is Viand. Not to mention Surry Hills' stalwart Spice I Am, Khao Pla in Macquarie Park, the Isan specialties at Yod in Haymarket, and Palisa Anderson's Chatswood branch of Chat Thai.

What I can say is that there has never been so many knockout Thai restaurants to choose from. Dismal weather and train delays are nothing when mood-lifting curry is around the next corner.

Vibe: Fresh and fiery family meal

Go-to dish: Baked tiger prawns with vermicelli ($28)

Drinks: Two beers, four wines, and a BYO corkage of $10 per bottle

Cost: About $110 for two, excluding drinks

This review was originally published in Good Weekend magazine