The primary ingredient in a traditional phở is rice noodles, specifically bánh phở. This Vietnamese noodle soup is known for its aromatic broth, which usually features beef or chicken. The rice noodles are flat, tender, and serve as the perfect vehicle for the flavors from the broth and additional toppings like fresh herbs, bean sprouts, lime, and chili. The dish is often garnished with sliced meat, either cooked or raw, which cooks in the steaming broth, creating a flavorful and satisfying meal. Each region in Vietnam has its own variation of phở, reflecting local tastes and ingredients.