Bun Thang Ba Duc is a small restaurant in Hanoi that serves Bun Thang, a traditional Vietnamese noodle dish. The dish is made with vermicelli noodles, chicken, egg, and herbs, and is served with a clear broth. The dish is simple but delicious, with a perfect balance of flavors. The restaurant's interior is also simple, with plastic chairs and tables, but the food is affordable and authentic.