I'm on the back of a Vespa, on my way to meet a gangster. Not that I know it yet. Night has descended and rain is slapping the tarmac with a fervent drumming. We're soaked to the bone as we pull up outside a restaurant called Oc Loan on a small side street in Ho Chi Minh City. Water troughs are set out like street stalls, displaying snails bigger than my fist, plump clams and glistening river prawns. Presiding over them is a man in ripped denim shorts and flip-flops, weighed down by thick gold chains, knuckle dusters and gigantic cuffs. Needless to say, he's not the maître d' I'd been expecting.

Inspired by Michelin's first restaurant guide to Ho Chi Minh, published in 2023, I'm taking a deep dive into the city's eclectic street-food scene on a scooter tour. "The owner here was a gangster," says my guide and driver Yen Navi, referring to our bling-laden host as he nods us over to plastic seats. "His wife ran the restaurant first. His gold chains attracted people and that's how Oc Loan became more and more popular."

Eating out in Vietnam's second city is never dull, as I'm beginning to discover. Frontman aside, Oc Loan has serious street cred with local snail- and seafood-lovers. It's packed, inside and out. Empty clam and mussel shells have been discarded on the spit-and-sawdust floor like cocktail sticks at a Spanish tapas bar. And the dishes that arrive are rustic, with many ingredients plucked from the nearby Mekong Delta. I'm not brave enough for the giant snails but happily tuck into juicy clams in an aromatic lemongrass broth, sizzling barbecued prawns and a platter of soft, smoky scallops with peanuts and spring onions.