Hai Duong sits about 57 km east of Hanoi on the road toward Hai Phong — close enough that most people pass through without stopping. That's a mistake, at least if you care about sweets. The city has been the production center for "banh dau xanh" (mung bean cake) for well over a hundred years, and the craft is specific enough to a handful of family workshops that the product from anywhere else just doesn't taste the same.
What Banh Dau Xanh Actually Is
At its simplest, banh dau xanh is a compressed cake made from split mung beans, sugar, and lard. That description undersells it. The texture when done well is dry and powdery at the surface, then gives way to a dense, faintly waxy interior that dissolves on the tongue in a clean, mildly sweet finish. There's no filling, no syrup, no gimmick. The quality lives entirely in the ratio of ingredients and the pressing.
Standard cakes are about 3 cm square and 1 cm thick, wrapped first in wax paper and then in foil, typically packed in gift tins of 20 or 40 pieces. The color runs from pale yellow to deep gold depending on how long the beans were roasted before grinding.
Why Hai Duong and Not Somewhere Else
Mung beans grow across Vietnam (베트남 / 越南 / ベトナム), so the geography question is legitimate. The short answer is that Hai Duong's version became commercially codified in the early 20th century, when a few workshops — most cited is Bao Hien Thanh, founded around 1908 — standardized the recipe and built distribution networks to Hanoi and the Red River Delta. The craft passed down through families, and those families stayed in Hai Duong.
The longer answer involves the local water (soft groundwater from the delta), the specific strain of small-seeded mung bean traditionally grown in Hai Duong and neighboring provinces, and the fact that the pressing molds used by old workshops are seasoned over decades. None of that is romantic myth — any pastry cook will tell you that fat absorption and moisture content shift with the mineral profile of water, and the local bean variety has a lower fiber-to-starch ratio than the larger beans grown in the south, which affects how finely you can grind it without losing cohesion.
Modern producers now use electric grinders and vacuum packaging, but the core recipe at reputable workshops hasn't changed much.
Photo by Vyvan BÙI VY VÂN on Pexels
The Main Producers Worth Knowing
Hai Duong city has dozens of shops selling banh dau xanh, but quality separates sharply.
Bao Hien Thanh on Nguyen Luong Bang street is the oldest name and the one most often brought as gifts to Hanoi (하노이 / 河内 / ハノイ). Their tins are the ones you'll see in the glass cases of Old Quarter souvenir shops, marked up about 30%. Buying at source in Hai Duong runs around 80,000–120,000 VND per tin of 20, depending on size and grade.
Nguyen Huong is the other household name, slightly more automated in production but consistent and widely available at their shops near the Hai Duong train station and bus terminal. Good for bulk buying if you're taking gifts north or south.
Smaller family workshops cluster around Nguyen Thi Minh Khai street and operate more like cottage producers — you can sometimes watch the pressing happen in open-front rooms. These batches move fast and are rarely packaged for long-distance travel, so you eat them within a day or two. That version, slightly softer and less desiccated than the vacuum-packed tin product, is noticeably better.
How to Eat Them
Paired with tea, specifically green tea or lotus tea. Not coffee — the fat in the cake and the bitterness of Vietnamese coffee compete in a way that neither wins. A few cakes alongside a pot of tra sen (lotus-scented green tea) is the canonical combination, and it works because the floral top note of the tea cuts through the richness of the lard.
They're also eaten as a between-meal snack, not a dessert course. You don't finish a bowl of "bun cha" and then reach for banh dau xanh. You eat them mid-morning or mid-afternoon, the same slot occupied by "banh chung" during Tet or sesame candy at festivals.
Shelf life on the vacuum-packed tin version is 3–6 months. The unwrapped workshop versions should be eaten within 48 hours.
Photo by Nguyễn Thị Thảo Hà (Ha Nguyen) on Pexels
Getting to Hai Duong
From Hanoi's Gia Lam or My Dinh bus stations, buses to Hai Duong run frequently and take 60–90 minutes depending on traffic. Cost is around 60,000–80,000 VND. The city is also on the Hanoi–Hai Phong rail line; trains take about 80 minutes from Long Bien station.
Hai Duong isn't a destination that demands a full day — most people combine it with a trip toward Hai Phong or Con Son-Kiep Bac pagoda complex. A two-hour stop in the city center is enough to visit a workshop, buy tins, eat lunch, and get back on the road.
Practical Notes
If you're flying out of Noi Bai (Hanoi), vacuum-packed tins pass carry-on security without issues — they're shelf-stable and under solid-food rules. Buy at the Hai Duong workshops directly rather than at Hanoi airport shops, where the same tins run 40–60% higher. For volume purchases, both Bao Hien Thanh and Nguyen Huong offer slight discounts at around 10 tins or more.
Last updated · May 26, 2026 · independently researched, never sponsored.
