Bun dau mam tom, the lunch that Hanoi lives for, is almost always bought on the street and often eaten there, too.
Like many Vietnamese dishes, it is assembled by the individual diner from a somewhat flexible roster of components. Fried tofu and pressed cold bricks of rice vermicelli are indispensable, as are cucumbers and branches of green herbs. Sausage and cooked pork may make an appearance. But the point of the dish, the nucleus that the other ingredients orbit around, is a fermented-shrimp sauce called mam tom.
Mam tom is the color of a day-old bruise. It has the insistent, nostril-permeating odor of old seafood left in some back corner of the fish market where the cats always seem especially agitated. Imagine scraping the anchovies off a couple of pizzas and leaving them out on the counter for the summer, and you have a good idea how mam tom smells.
Even in Vietnam, mam tom is divisive. The dish it anchors, bun dau mam tom, is not loved everywhere in the country, let alone abroad. It is, however, enjoying star treatment in New York City as the main focus of Mam, an evolving Vietnamese kitchen on the Lower East Side that has been operating off and on since September of 2020.
Like many food businesses born in the pandemic, Mam is hard to label. Its irregular schedule suggests a pop-up. After an initial six-week run, it paused for more than a year while one of the owners, Nhung Dao Head, had a baby. She and her husband, Jerald Head, who does most of the cooking, regrouped and brought Mam back last spring. They took another break this winter to go to Vietnam to visit with relatives, shop for ingredients they can’t buy in New York, and cook.
Since February, Mam has been open three days a week. In the manner of many pop-ups, menus are announced a few days in advance. (For the moment, reservations are sold through Hotplate, an online ordering platform.)
Unlike some pop-ups, though, Mam has a fixed address that it doesn’t share with anyone else, two doors up from Spicy Village on Forsyth Street.
On cool or rainy days, Mam is confined to its narrow dining room, which can seat 19 people at tables about as wide as surfboards. When the weather permits, though, the enterprise flows outdoors. The Heads will carry short plastic tables and matching plastic stools out to the sidewalk.
Sometimes they will also set up on the far side of Forsyth Street, in the roadway, next to the brick wall of a playground. Sitting on a plastic stool in the street eating tofu from a bamboo tray while pedestrians and dogs and e-bikes and regular bikes and mopeds pass in both directions may be as close as you can get in Manhattan to lunch hour in Hanoi.
My bun dau mam tom method is to start with a piece of tofu or noodles or something else dipped in mam tom. This is not just fermented-shrimp paste out of the jar; Mr. Head stirs it with sliced red bird’s-eye chiles and a few drops of fresh citrus, to make a sauce as delicious as it is terrifying.
I will follow this by chewing on a few herb leaves — besides tia to, or Vietnamese perilla, Mam usually has a more lemony variety of perilla called kinh gioi as well as heart-shaped leaves of fish mint, or diep ca, which does indeed taste of fish. The herbs taste so bright that after eating a few, and maybe a slice of cucumber, I am ready for more mam tom. This becomes a rhythm, cycling from funky shrimp sauce to green herbs and back again. It is a little bit like alternating repeatedly between a hot sauna and a cold pool, and it has a similar effect on the psyche.
Mam makes its own tofu; when fried, it is rich and chewy inside, more like mozzarella sticks than any tofu I’ve ever seen. Lately, Mr. Head has been filling out the bamboo bun dau mam tom platter with slices of cooked pork belly; grilled strips of pork intestine; and blood sausage stuffed inside whole, uncut pork intestine. The blood sausage, seasoned with fresh herbs and poached, may be the most flavorful item on the tray, although I haven’t had a chance to try the pork uterus served experimentally a few weekends ago.
Mr. Head, a former chef de cuisine at Di an Di in Greenpoint, Brooklyn, makes a few appetizers as well: chopped surf clam and fronds of snow fungus quickly marinated in lime juice with lemongrass and ginger, ceviche-style; mussels and pork with quantities of fresh dill in a springy, flat sausage; fish-sauce-marinated skirt steak that is on its way to becoming jerky.
The beef is nice on its own, but achieves liftoff when it has been dredged through a pile of ground chiles and edible ants that the Heads brought back from their last Vietnam trip. Among their other purchases were dried sea worms (made into a noodle soup with East Coast mussels and dill), coffee beans from the Central Highlands and mam tom from a small producer in the heart of fermented shrimp-paste country.
Many of the things that make Mam so exciting — the rare ingredients, the specials that show up out of nowhere, the menus that make few concessions to American palates — would be difficult if it were a real restaurant with a market rent and payroll to worry about. (Mr. Head typically works with one other cook, and they sometimes pitch in to help Ms. Head manage the front of the house.)
On the other hand, stability has advantages, too.
For now Mam is still hanging on in the tentative, experimental space that the pandemic opened up. It probably can’t keep going the way it has been, and you just have to hope that once it finds a way to survive for the longer term it can hold on to some of the things that have made it the most exciting place in the city to eat Vietnamese food.
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