Hoi An Xi Ma Sweet Soup: Decoding the Addictive "Pitch Black" Dish of the Ancient Town

Hoi An Xi Ma sweet soup, also known as Chi Ma Phu or black sesame sweet soup, is a traditional signature snack of Hoi An Ancient Town. This dessert originates from the Chinese community that migrated to Vietnam in the 17th century, and over time, it has blended with local cuisine to become an iconic dish of Hoi An. 

In terms of appearance, Xi Ma sweet soup has a glossy black color from finely ground black sesame seeds, looking quite "unusual" to first-timers. However, this is no ordinary sweet soup, but a delicate combination of natural ingredients such as black sesame, sweet potato flour, tapioca starch, sugar, pennywort, Chinese knotweed (rau mơ), and water from the ancient Ba Le Well. The dessert is usually cooked into a thick, smooth, viscous paste and served hot to retain its maximum rich and aromatic flavor.

Not only a delicious snack, Hoi An Xi Ma sweet soup also carries high nutritional value. Black sesame is rich in antioxidants, iron, calcium, and vitamin E, which help nourish the blood and benefit hair and skin. According to traditional medicine, this dish has cooling and detoxifying effects, making it very suitable for the hot and humid climate of Central Vietnam. If you are traveling to Hoi An, this is definitely a must-try dish to feel the rustic yet refined essence of ancient town cuisine.

The name “Xi Ma” or “Chi Ma Phu” comes from Hokkien (a dialect of Chinese), the origin of Hoi An's Chinese community. In Hokkien, “Chi Ma” or “Xi Ma” means black sesame seeds, while “Phu” (or “Fu”) refers to the smooth, puréed texture of the soup after grinding and cooking. This name is not only simple but also reflects the refinement in its preparation, where black sesame seeds are finely ground to create its signature thickness.

The imprint of Chinese culture in Hoi An Xi Ma sweet soup is vivid evidence of Hoi An's bustling trading history during the 16th and 17th centuries. At that time, Hoi An was an international trading port, attracting merchants from China, Japan, and Europe. The Chinese community (mainly from Fujian) brought along their hometown cuisine, and the black sesame dessert was gradually adapted to incorporate local ingredients such as pennywort and sweet potato flour.

Today, Xi Ma sweet soup is not just a dish, but also a cultural heritage contributing to the diversity of Hoi An cuisine – a place where Vietnamese traditions and Chinese-community influences blend seamlessly. 

Cooking traditional Hoi An Xi Ma sweet soup requires meticulous care and heirloom secrets passed down through the Chinese community. Below is a detailed process based on ancient methods, allowing you to try making it at home:

• Ingredient Preparation:
  • 200g high-quality black sesame seeds.
  • 100g sweet potato flour or tapioca starch.
  • 150g white sugar or rock sugar.
  • Pennywort and Chinese knotweed juice (optional, about 100ml to enhance cooling properties).
  • A little tapioca flour to create thickness.
• Preparing the Black Sesame: Soak black sesame seeds in water for about 2-3 hours to soften, then rinse thoroughly and toast in a hot pan until fragrant. Toast over low heat so the sesame doesn't burn, preserving its natural aroma.
• Grinding: Pour the roasted sesame into a blender with a little water and grind finely into a smooth paste. This is a crucial step to achieve its characteristic smooth "phu" texture.
• Cooking the Soup: Boil about 1 liter of water, add sugar and sweet potato flour, stirring until dissolved. Then pour in the ground sesame paste, stirring constantly over low heat to prevent clumping. Cook for about 20-30 minutes until the soup thickens and becomes velvety smooth.

Note: The secret of the Chinese in Hoi An is using natural herbs to balance the sweetness, making the dish not only delicious but also good for health. 

Hoi An Xi Ma sweet soup easily lingers in memory not because of complexity, but thanks to its well-balanced flavor. The moderate sweetness of sugar, the natural richness of roasted ground black sesame, and the distinct aroma from traditional cooking techniques create a harmonious, easy-to-eat dish. The dense black color might make some people hesitant at first, but upon tasting, the dessert gently melts on the tongue, leaving a cool and pleasant sensation thanks to herbal ingredients like pennywort or Chinese knotweed.

The reason many people "remember it after just one bite" lies in three clear points. First, black sesame provides a mild, non-greasy richness. Second, the sweet soup offers a quick energy boost, perfect for resting after walking around the ancient town. Finally, its rustic, familiar flavor makes this dish feel welcoming, like an intrinsic part of Hoi An's traditional food culture. Many tourists admit that they seek out Xi Ma sweet soup every time they return to the ancient town.

Savoring Hoi An Xi Ma sweet soup right in the heart of the ancient town is an unforgettable experience. Imagine sitting on a small bamboo stool by the sidewalk under shimmering lanterns, sipping spoonfuls of piping hot sweet soup in the chilly evening air of Hoi An. The dish is usually sold at street food carts or tiny stalls, open from early morning to late afternoon, costing only around 10,000 - 20,000 VND per bowl.

For the full experience, visit Hoi An during autumn or winter, when the cool weather highlights the cozy warmth of the sweet soup. Combined with strolling around, visiting the Japanese Covered Bridge, or shopping for lanterns, you will truly feel the connection between gastronomy and culture.

If you are looking for authentic places to try Hoi An Xi Ma sweet soup, here are famous addresses:

• Mr. Thieu's Vendor: 45/17 Tran Hung Dao Street, Minh An Ward, Hoi An
• Mrs. Thao's Stall: Located on Tran Phu Street, famous for sweet soup served with refreshing pennywort. 
• Ms. Thi's Stall: Near Hoi An Market, a small stall always crowded with customers thanks to family herbal secrets. 

Amidst the slow pace of life in the ancient town, Hoi An Xi Ma sweet soup exists as a humble yet enduring culinary gem over time. Requiring no flashy presentation or elaborate etiquette, this sweet soup wins over diners with its simple, comforting taste deeply tied to the culinary memory of a long-standing community. Enjoying Xi Ma sweet soup is also a way to gain a deeper understanding of Hoi An – a place where the most ordinary things possess a lasting vitality that leaves visitors forever longing to return.