Peppery spinach, tender beef fillet and a flavoursome broth make Ken Hom's quick to cook Vietnamese Soup a sensation. This light soup is typical of the subtle cuisine of Vietnam. It is easy to make, and many of the steps can be done in advance.
Bring a large pan of salted water to the boil and blanch the spinach leaves for a few seconds until they are just wilted. Drain well and refresh in cold water to prevent further cooking. Drain again, squeezing out excess water.
Combine the steak strips with the shallots, garlic, 1 tablespoon of fish sauce and a grinding of black pepper, and then set aside.
Just before you are ready to eat, bring the chicken broth to a simmer in a large saucepan and stir in the remaining fish sauce, together with the lemon juice, sugar and chili.
Stir in the blanched spinach and the beef, with its marinade.
Bring the soup back to simmering point; add another good grinding of black pepper and serve at once.