Khun Pakin Thai, Hammersmith

You think I'd have learned by now, quite honestly. The rule is, if I enter a Thai restaurant and it's full of Thai people, I do not ask for anything even approaching a 'medium' heat. I like to think I can take quite decently spicy food on a good day, and never shy away from some of the hottest (within reason) dishes in Mexican or Indian food, but the levels of heat applied to even the most entry-level Thai dishes can be astonishing, and humbling.

Of course, it having been so long since I had been exposed to truly authentic Thai spice levels, I had let my guard down. Like the pain of childbirth (so I'm told), the agony of a chilli bomb fades as time goes on, and it had been so long since my last visit to a truly dangerously authentic Thai experience (the Heron in Paddington) that I had somehow convinced myself I handled it pretty well (my friends with me that night will remind me: I did not). Khaosarn (Clapham Junction) I love you, but you have quite sensibly noticed your catchment areas consist largely of people not really accustomed to the full chemical attack of a genuinely Thai-spiced laab, and while the food is easily enjoyable, it all ends up being, well, quite Clapham-friendly.

Not so a Khun Pakin. On ordering the main courses, you are asked where on a scale of 1-5 we would like the spice level set. With serene assuredness, we replied 4. An expression somewhere between surprise and concern flashed across our server's face.

"4 is very hot, I would recommend 2."

Clearly, she was judging us based on the fact we were the only two non-Thai faces in the room and needed to be protected from ourselves. We'd show her.

I and my dining companion exchanged knowing smiles, then turned back to the server, "OK, let's compromise. We'll have the tiny pickled crab salad and raw prawn salad in a 3, and the deep fried pork neck (seriously, how spicy can pork neck be) as a 4.", then with a raised eyebrow and wry grin for extra dramatic effect, "Do you think we could cope with that?".

She paused for a second, presumably weighing up how much energy she could put into persuading two smug idiots not to damage themselves vs just getting on with her evening serving a rammed pub. She chose the latter and trotted off, shaking her head slightly.

First to arrive were mu ping, skewers of grilled pork with lovely highlights of charring from the grill, tender and glistening with a complex sweet glaze. Effortlessly easy to enjoy, and a superb example of their kind, they were nonetheless not quite the rollercoaster of fire and flavour we were bravely preparing ourselves for. We rolled our eyes at each other at the naivety of our waitress. Didn't she know we were seasoned food adventurers, with stomachs of steel? Was this it?

Next the pork neck. First impressions were of a beautifully tender fillet in a crunchy tempura-like batter, sliced atop a colourful salad. The pork itself was faultless, greaselessly fried and boasting perfect textures, but the salad and associated dressing completed the dish, offsetting the grease and crunch with sweetness and what at first seemed like quite a mild heat. At first. The first few mouthfuls were pleasant but unassuming, a bit like a mildly chillified vinaigrette. We were seriously considering getting up and asking if they'd not changed the other for our own good and downgraded the chilli level. Then, within a minute or so, all hell broke loose. The chilli heat built from mild to hot to severe with terrifying speed, and we went from one minute laughing about the patronising server to something similar to that diner scene from Dumb & Dumber.

It was, as we had been told perfectly clearly, way too hot for us. Gasping for beer and tears streaming down or reddened faces, we ploughed on, partly because we could sense a room full of bemused Thai eyes on us but also, despite the pain, it was genuinely brilliant stuff. Tiny pickled crabs were exactly that, crunched whole to release complex seashore flavours involving sea urchin and seaweed, alongside a good hit of earthy brown crab. They were woven into a papaya salad that also hurt to eat, but in a good way.

Raw prawn salad used clearly excellent live (I assume) prawns, with a smooth, solid texture of healthy animal and another colourful and distressingly hot salad. The latter stages of the meal were spent in kind of feverish panic, desperately trying to hide our sweaty, panting faces from the rest of the room, most of whom were knocking back the same stuff as if it was a McDonald's Happy Meal. As a final humiliating act of retribution, we were forced to pay our bill (£27 a head, very decent really) to the same person who'd tried to talk us into downgrading the chilli levels initially. She took a good long look at the broken individuals in front of her and finally asked, with a deadpan expression, "how was your meal?". "You were right, I'm so sorry" was all I could croak in return.

Don't let our stupidity put you off though. If I went back to Khun Pakin (and I very much hope to), I'm going to order everything at spice level 1, which I'm sure would still pack a punch but be less likely to trigger a full cardiac arrest. And it will still be brilliant because this kind of intelligently constructed, imaginatively sourced food (really, where else are you going to get tiny pickled crabs?) is always worth the effort. There's a special whole blue crab salad which you have to order a week in advance which I spotted with some measure of jealousy being delivered to other tables. There's a whole other menu section of soups and curries that we didn't even try. You could have a lot of fun here, working your way through it all.

Just don't do what I did, and please accept the sage advice of your server who is, after all, just making sure your memories of eating at Khun Pakin are of the superb fresh seafood and expertly fried protein, and not gently sobbing as you attempt to douse the inferno in your mouth with yet another cold beer. Consider myself chastened, and duly reminded that when it comes to authentic Thai food, the best places don't hold back, and nor should they.

8/10