Bún riêu cua (crab paste vermicelli) is Vietnamese vermicelli, served in a tomato broth and topped with crab or shrimp paste. In this dish, various freshwater paddy crabs are used, including the brown paddy crab found in rice fields throughout Vietnam. These freshwater crabs are pounded in the shell until they consist of a fine paste. This paste is strained and the crab-infused liquid is a base for the broth called “riêu cua” (along with tomato). Other ingredients include: fried tofu, mẻ (ferment) or bỗng (fermented grains), Garcinia multiflora Champ., annatto seeds (hạt điều màu) to redden the broth, pig's blood, split water spinach stems, shredded banana flower, rau kinh giới (Elsholtzia ciliata), spearmint, perilla, bean sprouts and chả chay (vegetarian sausage). It is one complex dish.