Pho is the ultimate do-it-yourself Asian cuisine. It's peasant food, lacking any pretension, based on frugality and the whole-food ethos that demands the use of any possibly edible bit of everything. Pho broth is slow-cooked, simmered and reduced simple stock kicked up with onions boiled until translucent, green onion stalks and spices. There's always salt but never pepper; sometimes star anise and cinnamon, often lemongrass and soy. Every minute the broth sits on the stove changes its character in small ways. Every minute it sits before you, cooling as you eat, changes it. But there's one thing you can be sure of at Pho 2000: No matter when you arrive, you'll find the best pho in town.