Vietnamese Pho Bo (Beef Noodle Soup)

Steps

1. 1

   Parboil the bones

   • Put the beef bones in the 12-quart (11 L) stockpot and add the 3,800 ml (4 qt) cold parboiling water so the bones are fully covered.
   • Bring to a full boil over high heat (about 15 minutes), then boil hard for 10 minutes.
   • Grayish-brown foam and scum will rise to the surface.

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   Ready when: Thick gray foam covers the surface and the water looks murky

   Tip: This step is what keeps the final broth clear instead of cloudy, so don't skip it.

2. 2

   Rinse bones and pot

   • Carefully drain the bones into a colander in the sink.
   • Rinse each bone under running warm water, scrubbing off any dark scum or bits of blood with your fingers.
   • Wash the stockpot well to remove all residue, then return the clean bones to it.

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   Ready when: Bones look pale and clean with no dark scum clinging to them

   Tip: Use oven mitts and drain away from you; the pot and steam are very hot.

3. 3

   Char onion and gingerOven 500°F / 260°C

   • Position an oven rack 4 inches (10 cm) below the broiler and heat the broiler to high (about 500°F / 260°C).
   • Place the onion halves cut-side down and the ginger on the foil-lined baking sheet.
   • Broil 6–8 minutes, flip, and broil another 6–8 minutes.

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   Ready when: Onion edges are blackened in spots and the ginger is blistered, fragrant, and softened

   Tip: Watch closely; broilers vary and the char should be dark in patches, not burnt all over.

4. 4

   Toast the spices

   • Combine the star anise, cinnamon stick, cloves, coriander seeds, and fennel seeds in the small dry skillet.
   • Toast over medium-low heat, shaking the pan often, for 2–3 minutes.
   • Tip onto a square of cheesecloth, gather the corners, and tie with kitchen twine into a bundle.

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   Ready when: Spices smell strongly aromatic and the coriander seeds are a shade darker

   Tip: Pull the pan off the heat the moment the spices smell fragrant; burnt spices make the broth bitter.

5. 5

   Start the broth

   • Add the charred onion, ginger, spice bundle, and 4,700 ml (5 qt) cold water to the pot with the clean bones.
   • Bring to a boil over high heat, then reduce to low so the surface barely bubbles.
   • Skim off any foam that rises during the first 20 minutes with a skimmer or large spoon.

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   Ready when: Surface shows only a few lazy bubbles and the liquid is fairly clear

   Tip: Never let the broth boil hard after this point; a rolling boil emulsifies fat and clouds the broth.

6. 6

   Prep steak and garnishes

   • While the broth simmers, put the flank steak in the freezer for 20 minutes.
   • Meanwhile, slice the white onion paper-thin and soak in cold water; slice the scallions; chop the cilantro; rinse the bean sprouts; pick the Thai basil leaves; cut the limes into wedges; and slice the chiles, if using.
   • Remove the steak, trim it, and slice against the grain as thinly as possible.
   • Arrange the steak on a plate, cover, and refrigerate.
   • Arrange the garnishes on a serving platter.

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   Ready when: Steak slices are almost translucent and about 1/16 inch (2 mm) thick

   Tip: A well-chilled, firm steak slices far more thinly than a soft one; use your sharpest knife.

7. 7

   Simmer the broth

   • Partially cover the pot and keep the broth at a gentle simmer on low heat for 2½ more hours (3½ hours total).
   • Stir rarely and top up with a little hot water if the level drops below the bones.

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   Ready when: Broth is deeply fragrant, tastes rich and beefy, and the meat on the bones is very tender

   Tip: If the broth smells strongly of cinnamon or anise early on, lift out the spice bundle after 2 hours.

8. 8

   Strain and season

   • Lift out the bones, onion, ginger, and spice bundle with tongs and discard (or pick off any tender meat to add to the bowls).
   • Pour the broth through a fine-mesh strainer into a clean large pot.
   • Skim excess fat from the surface with a ladle.
   • Stir in the fish sauce, rock sugar, and kosher salt until dissolved, then taste and adjust with more fish sauce or salt.

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   Ready when: Broth is clear, amber, and savory with a hint of sweetness; it should taste slightly over-seasoned since noodles will dilute it

   Tip: Season in small increments; fish sauce brands differ widely in saltiness.

9. 9

   Cook the noodles

   • Bring the 4-quart (3.8 L) pot of water to a boil over high heat.
   • Add the rice noodles and cook according to the package directions, usually 5–8 minutes, stirring once or twice to keep them from clumping.
   • Drain, rinse briefly under warm water, and divide among 6 deep bowls.

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   Ready when: Noodles are soft and tender with a slight chew, not mushy

   Tip: Cook the noodles just before serving; they turn gummy if left to sit.

10. 10

    Assemble and serve

    • Return the broth to a rolling boil over high heat.
    • Top each bowl of noodles with several slices of raw flank steak, a spoonful of drained white onion, scallions, and cilantro.
    • Ladle about 1½ to 2 cups (350–500 ml) of boiling broth over each bowl; the hot broth cooks the beef within a minute.
    • Serve immediately with the platter of bean sprouts, Thai basil, lime wedges, and chiles, plus hoisin and sriracha on the side.

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    Ready when: Steak slices turn from red to mostly gray-brown with a hint of pink in the center

    Tip: The broth must be at a full boil when it hits the bowl or the thin steak won't cook through. Leave any steak slices you want more done submerged for an extra minute.