- 6 ounces dried rice-stick noodles (rice vermicelli)
- 1/4 snow peas, cut diagonally into 1/4-inch strips
- 1 cup sliced shallots
- 3 (1/8-inch-thick) slices fresh ginger, smashed
- 1 teaspoon minced fresh serrano chile, including seeds, or to taste
- 1 tablespoon vegetable oil
- 3 1/2 cups beef broth
- 1 3/4 cups water
- 1/2 pound thinly sliced rare roast beef (from deli counter), torn into pieces
- 6 ounces fresh bean sprouts
- 1/4 cup loosely packed fresh cilantro leaves
- 1/4 cup loosely packed fresh basil leaves, torn if large
- 1/4 cup loosely packed fresh mint leaves
- 3 tablespoons Asian fish sauce, or to taste
- 3 tablespoons fresh lime juice
- Cook noodles in a 4-quart pot of boiling water (not salted) 4 minutes, then add snow peas and boil 1 minute. Drain in a colander and rinse under cold running water to stop cooking. Drain well. Divide noodles and snow peas among 4 large soup bowls.
- Cook shallots, ginger, and chile in oil in same pot over moderate heat, stirring occasionally, until shallots are browned, 7 to 8 minutes. Add broth and water and simmer, uncovered, 10 minutes.
- While broth is simmering, divide roast beef, bean sprouts, and herbs among soup bowls with noodles.
- Discard ginger from broth and stir in fish sauce, lime juice, and salt to taste. Ladle broth into bowls and serve immediately.