The giant water bug has dark, tear-drop eyes and is spreading an ooze of disgusting across my palm. After being steamed, it is cut into small slices and placed delicately on a plate.
I brace myself. The insides of the bug gently cover my palate, releasing a rich, velvety perfume and the strong, sweet taste of green apples.
This is typical of food in Vietnam: scrumptious, well-balanced flavours, an unexpected delight. There are prawn summer rolls. There are mung bean pancakes wrapped in rice paper. There are dumplings, noodle soups in love potion broth, and claypot pork belly. And a culture of sitting on tiny stools sipping coffee that is more sweet condensed milk than coffee, and that makes your body float in a euphoric haze of sweetness.
But the food in Vietnam is much more than simply pleasuring the tastebuds. It is a record of the country's history, and the key to opening its heart.
In Hanoi, the syrup of the water bug is the secret ingredient of banh cuon - thin, steamed pancake stuffed with pork and mushrooms, and topped with fried shallots, shrimps and a jungle of coriander.
But it's the dipping sauce that gives it that extra zing. Lime and sugar, chili and fish sauce, and a drop of ca cuong - juice from the bug, which live in surrounding rice paddies.
The essence of the juice is produced by a pheromone from the male that attract females. Consuming it, the Vietnamese say, transforms men of all ages into virile, horny rabbits. I seemed totally immune to this.
The sauce leaves a sweet aftertaste to the savoury meal. And this is the secret to Vietnamese cuisine: the perfect balance of sweet, salty, spicy, sour and bitter.
This is nowhere better on display than in the cooking classes throughout the country, which are as much about the cuisine as they are about demonstrating that anyone with two hands can make the most delicious of dishes.
Classes from Hanoi to Hoi An in the middle of Vietnam to Ho Chi Minh City in the south showcase a variety of fresh herbs and spices: turmeric, coriander, water mint, basil, mustard leaf, chili, and almost always accompanied by lime and fish sauce.
Each class has the most basic instructions: slice a shrimp in half, place inside rice paper with everything else, and roll. You'd have to be physically incapable of using your hands to stuff up this delightful summer roll.
Many of the classes take place in restaurants that started from humble beginnings and mirror the history of the country. They scratched a living as market stalls during the lean communist years, but now earn a great living off the lifeblood of the country's economy: foreign tourists.
But there are causes for concern. Every patch of land in Vietnam is Government-owned, and leased. Some of the markets that have been around since the beginning of time are now being moved to make way for foreign interests prepared to pay more expensive leases.
For now the Chau Long market in Hanoi is still there, and full of treats from the sublime to the strange.
Banh ran seem to exist solely to test the maximum levels of magnificence that can radiate from your mouth. These dumplings are filled with mushroom and shrimp, and topped with sesame seeds. When deep-fried, they puff up like a mini-balloons and fill with air, making them gorgeously light.
Many stalls have several different types of eggs, from tiny quail eggs to duck eggs sitting in a wire basket. The basket is covered at night so if a developing duck foetus hatches, it remains trapped under the wire.
To eat, crack the egg into a small bowl and lace the contents - half-formed feathers and eyes and beak - with ginger and salt. It has two distinct flavours: egg, and insides.
Just around the corner is a plate of silk worms. They are clear and look as if they are little crunchy capsules of sweetness, until I bite into them and am repulsed by the soft texture.
The leisurely pace of our stroll through the market is very different to the onslaught upon entering Ms Vy's restaurant Bale Well in Hoi An.
As soon as we sit down, we are attacked from all flanks by her minions. They are armed with plates of greens, pickled vegetables, deep fried spring rolls and pork on a stick.
They show us what to do: take a piece of round rice paper, overfill it with everything, and then roll tightly. Dip and eat. If you weren't paying attention, no matter. They simply roll it for you, and insert it into your mouth. Resistance is useless. This is almost forced eating without consent, food rape.
Except that consent is automatic when each bite unleashes an explosion of flavours: bitter, sweet and savoury, dipped in spicy, and a soft exterior with a deep fried core. Washed down with beer also held to your mouth by one of the waitresses. If you were so inclined, you could just sit there with your mouth open and then leave totally filled with beer and food.
Other dishes in Vietnam are a clear nod to the French, who colonised Vietnam from 1887 to 1954. The famous pho bo - beef noodle soup - is considered one of the world's best street eats. The French used to slaughter water buffalo and give the bones to the locals, who used it to make a brew. And the broth is the key to the intense flavour, usually made by boiling a marrow-filled backbone with char-grilled shallots and ginger for 15 hours.
But the broth is far more important than just satiating hunger. It is the traditional true love potion. Time and again during our stay we came across people in their 20s talking about the importance of a good broth in luring Mr Right.
Old-fashioned as it sounds, it seems a great sense of humour, supreme intellect and a radiant smile count for little if she suffers from bad broth. No matter how horny on water bug juice he is.
GETTING THERE: Singapore Airlines flies daily Auckland to Hanoi with a stopover in Singapore.
TOURS: An Intrepid Travel Real Food Adventure tour of Vietnam is a 12-day trip from Hanoi to Ho Chi Minh City and includes stops in Hoi An, Hue, Halong Bay and a homestay on the Mekong River. Cost is $2295 not including flights, which covers most food, all accommodation, transport, cooking classes and local English-speaking guides.
• Derek Cheng travelled to Vietnam as a guest of Intrepid Travel.