- 1 1/2 pounds beef top sirloin, fat trimmed, cut lengthwise in half
- 3 tablespoons minced lemongrass
- 4 tablespoons fish sauce (nam pla)
- 1 1/2 tablespoons soy sauce
- 1 1/2 teaspoons sugar
- 3 garlic cloves, minced
- 4 tablespoons peanut oil
- 3 tablespoons fresh lime juice
- 1 large shallot, minced
- 1 tablespoon minced seeded serrano chile
- 1 bunch mustard greens, torn into 1-inch pieces
- 1 head of bok choy, torn into 1-inch pieces
- 2 cups thinly sliced red onions
- 1 cup (packed) opal basil or regular basil leaves
- Freeze beef 30 minutes. Using large knife, thinly slice beef crosswise. Mix meat, lemongrass, 3 tablespoons fish sauce, soy sauce, 3/4 teaspoon sugar, and garlic in large bowl. Sprinkle generously with black pepper. Let stand at room temperature 30 minutes or chill up to 3 hours.
- Whisk 3 tablespoons oil, lime juice, shallot, chili, 1 tablespoon fish sauce, and 3/4 teaspoon sugar in bowl to blend. Season dressing with salt and pepper. Let stand at room temperature 30 minutes.
- Place mustard greens, bok choy, onions, and basil in large bowl. Add 3/4 of dressing; toss to coat. Season salad with salt and pepper.
- Heat 1 tablespoon oil in heavy large skillet over high heat. Working in 2 batches, stir-fry meat until cooked to desired doneness, about 35 seconds for rare. Add to greens. Add remaining dressing and toss to combine. Serve immediately.
- Available at Asian markets and in the Asian foods section of many supermarkets.
- Opal basil has purple leaves and a milder flavor than sweet basil. It is available at Asian markets and some supermarkets.