If you've only met vermicelli in a soup and thought "thin noodles," you're missing the point. Glass vermicelli recipes work because fen si is built to absorb — it pulls broth, sauce, and steam into itself until the noodle tastes more like the dish than the starch it started as. That single habit is why it shows up in braises, clay pots, and seafood spreads across Chinese home cooking.
What exactly is fen si?
Fen si (粉丝) are made from mung bean or sweet potato starch, not wheat. They come dried, nearly transparent, and turn into slippery, springy strands once soaked. Because there's almost no gluten, they don't get doughy — they get infused. That's the difference between vermicelli and, say, wheat noodles: one carries flavor, the other mostly carries itself.
Why it soaks up everything
- Starch structure is porous once hydrated, so liquid moves in fast.
- It has almost no taste of its own, so it takes on whatever it cooks with.
- It holds heat and sauce, so the last bite is as flavorful as the first.
Three dishes that show it off
The classic is蚂蚁上树 (ant-climbing-tree) — tiny bits of pork clinging to vermicelli that have drunk a savory sauce. Then there's garlic shrimp vermicelli, where the noodles sit under the shrimp and catch every drop of garlic oil. And the clay-pot version braises bok choy and pork together so the strands finish silky and loaded. Each is on HǎoWèi with a full bilingual recipe.
How to soak without turning to mush
- Use hot, not boiling-rolling, water for a gentler soak.
- Cut the softened bundles with scissors so they're easy to eat.
- Add them late in braises — they need minutes, not the whole cook.
A quick buying note
Mung-bean vermicelli stays firmer and clearer; sweet-potato versions are a touch chewier and a bit grey. Both work, but mung bean is the safer pick for soups where you don't want them to break apart.
