Vietnam (Hanoi); pho documented c. early 20th century; likely influenced by both Chinese noodle soup traditions and French pot-au-feu; pho became a national dish through the 20th century.
Beef pho — the great Vietnamese noodle soup — is naturally gluten-free in its traditional form: rice noodles, a bone and charred-aromatics broth seasoned with fish sauce, and protein. The single gluten concern is the hoisin and sriracha typically served on the side, which contain wheat in standard formulations — selecting GF versions of these condiments, or omitting them and providing lime, chilli, and fresh herbs instead, makes pho a completely GF meal. The broth is the preparation's entire investment: beef bones (ideally a combination of marrow bones and knuckles), charred onion and ginger, and the canonical spice blend (star anise, cloves, cinnamon, cardamom, fennel) simmered for minimum 8 hours, skimmed frequently, and strained through a fine mesh. The result — a clear, deeply flavoured, lightly sweet broth with the distinctive fragrance of star anise and charred aromatics — is one of the world's great preparations.
Blanch the bones first — bring to a boil in cold water, drain, and rinse; this removes blood and impurities for a clear broth Char the onion and ginger until blackened directly over flame or under a grill — this is the non-negotiable flavour step Toast whole spices before adding — blooming releases fat-soluble aromatics Skim frequently during the 8-hour simmer — every 30 minutes in the first 2 hours; the clearer the broth, the more it reads as quality Strain through a fine mesh before seasoning — all solids out before the final seasoning with fish sauce (GF) and rock sugar Rice noodles cooked separately and added to bowls per service — never cook noodles in the broth
The ratio: 1kg bones to 3 litres water is the professional standard — this produces a rich, gelatinous broth that is neither thin nor too concentrated A small piece of dried tangerine peel added with the spices in the last hour gives a subtle citrus depth characteristic of some regional versions Rock sugar is traditional for a gentle sweetness that balances the fish sauce's salinity — granulated sugar is an acceptable substitute but lacks the subtle complexity
Not blanching the bones — impurity-laden broth becomes cloudy and develops off-flavours Short simmering time — 8 hours minimum is the professional standard; less time produces a flat, thin broth Not skimming — scum left in the broth makes it murky and grey Over-seasoning during cooking rather than at the end — the broth reduces as it cooks; season only when the reduction is complete Using regular hoisin/sriracha without checking for GF status — these condiments typically contain wheat