The banh mi sandwich is an archetype of fusion cuisine. The Vietnamese street food favorite originated in Saigon in the early 20th century during the period of French colonization, and the typical components—including mayonnaise, pâté, and the all-important baguette that holds it all together—clearly show that Western influence. But the banh mi roll isn’t a standard French baguette: It’s lighter and crispier, and it shows how a different cultural perspective can improve upon something as essential as a loaf of French bread.
In fact, "banh mi" describes something uniquely Vietnamese. The name actually translates as "bread," and it has come to refer to the iconic sandwich as well. The bread in question has a thin, flaky crust and is soft in the middle, unlike traditional French baguettes, which are chewier with a harder exterior.
Vietnamese cuisine is chock-full of fresh herbs and vegetables, seafood and lean proteins, and bright condiments. (That thick slick of buttery mayonnaise on your last banh mi? Definitely a French influence.) Phi Pham, co-owner of a pair of Boston banh mi shops, Phinista Cafe and Bánh Mì Ơi, explains that the airy bread is particularly suited for the Vietnamese palate.
"It’s not a ‘super size’ culture," Phan says. "Because the banh mi is lighter in all aspects, it acts as a lighter vessel."
There are a few ways Vietnamese bakeries can achieve this quintessential crispness. Some recipes call for rice flour along with a higher-protein bread flour, a blend which can contribute to the light and airy texture. But that’s not a requirement, Nguyen says. The proprietary banh mi recipe she commissions for Soall from a local baker uses all-purpose flour.
Convection heat helps the rolls rise higher while they are baking, resulting in the desired fluffy crumb. Adding a pan of water to the oven to produce steam, or gently spraying the loaves with water a couple times throughout the bake, contributes hydration and can help the baguettes get pleasantly poofy.
The main technique, however, involves the shaping.
Rather than the gentle, repetitive folding technique that produces the tender texture of Parisian-style baguettes, Vietnamese bakers develop their gluten by vigorously whipping the dough with a machine mixer for a short amount of time, then rapidly slapping the loaves into shape before a long proof, Nguyen says.
"You can mix it by hand but I don’t think that’s going to yield the best, fluffy bread," Nguyen says.
It takes skill—and a controlled environment. She tried baking her own banh mi for Soall, but there were days the loaves would turn out as hard as baseball bats, she says. It’s a reason why even the highest-rated banh mi shops don’t always bake their own breads. Specialty bakeries abound in areas with a large Vietnamese diaspora, such as Boston and New Orleans.
So, while there may not be the banh mi without France’s influence on Vietnam, without the Vietnamese-perfected banh mi bread, this signature sub could be just any old sandwich.