In a large pot of boiling water, heat the vermicelli for a few seconds, using a strainer to lower them into the water. Drain and divide the noodles among four bowls.
Top the noodles with slices of the cooked and raw beef, bean sprouts, onion and green onion. Cover with the hot broth. Season with pepper. Serve, letting everyone garnish their own soup with the fresh herbs, chili pepper, lime wedges and sauces.
Note
Freeze the raw beef for 2 hours to make it easier to slice thinly.