Pho is a Vietnamese soup that's a combination of a deeply flavorful broth, rice noodles, thinly-sliced meat, and fresh herbs. The word "pho" is thought to come from the French word feu, meaning "fire", referencing the long simmering process that creates the broth. The broth is the essence of pho, and is traditionally made by simmering beef bones, ginger, star anise, cloves, cinnamon, and other spices for hours.