Phở Đuôi Bò (Vietnamese Noodle Soup with Oxtail) Recipe

By
Tam Ngo
Tam Ngo was an early contributor to Serious Eats.
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Updated May 15, 2019
A bowl of Vietnamese pho topped with fresh herbs

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Since we'll be stuck in dark drizzle for months to come, let's talk about phở, a perfect food for chasing away the doldrums of winter.

What Is Phở Đuôi Bò?

Phở bò is a Vietnamese beef noodle soup; phở đuôi bò is one made with oxtail. Regardless of meat choice or spice, the prototype is plush with the mouthfeel of gelatin, springy noodles, and bright herbs.

Phở originates from northern Viet Nam but the whole country sups the soup with patriotic zeal. Phở broth in the north tastes honestly of the meat and bones it's cooked with. The further south, the more likely you'll find it spiked with the warmth of anise, clove, cinnamon, and the like.

My-Man-of-Eternal-Patience and I have been tinkering with our recipe for several years now. Starting with Mai Pham's ingredients and Andrea Nguyen's tips, we threw in the accumulated wisdom of a few Vietnamese mums for good measure.

Roasting vs. Parboiling the Bones

In prior takes, we left the oxtails with fat intact and skimmed only afterwards. In this version, we trimmed the fat before simmering the tails to see if this saved time or hurt flavor.

French-trained cooks eschew parboiling and advocate pre-roasting the bones to build a deeper broth. Vietnamese cooks skip the roasting but parboil to create a cleaner broth. For each technique, you'll find yay-sayers on both sides. We decided to do a taste-test to see if one method yielded more favorable results.

More Time = More Awesome?

In this round of experimentation, we also increased the simmering time by 20-percent. After finding a 8-hour broth to be enormously richer than a 4-hour broth, we figured a 10-hour broth would be nothing short of effin' awesome.

Cinnamon sticks, star anise, cardamom, and peppercorns for pho broth
Spice mix, cha cha cha.

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The Results

Epic. Fifteen pounds of oxtail + ten hours = four gallons of two broths. I'm still cleaning blood from under my fingernails.

Fat Tails vs. Lean: Interestingly, we found that the Asian grocer H-Mart tends to sell thick, uniform cuts of oxtail with more meat than fat. Generic supermarkets such as Wegman's sell oxtail, variably sized, with rinds of yellowed fat and substantially less meat.

In the past, leaving the tails with fat intact gave us a impressive strata to skim afterwards. But not all the fat seemed to rise to the top. The broth had stretched squiggles I originally pegged as gelatin. I now suspect that what we saw was residual fat captured in gelatin. (This is based on sight and comparative mouthfeel, but I'm dying to know if this jives with science.)

In this experiment, we trimmed two pounds of fat pre-simmer and skimmed another half pound post. Upon serving, we reserved roughly the same amount of liquid fat in the soup as in earlier versions. And while the flavors of the soup still dazzled, it didn't luxuriate in the mouth as it did before.

Roasting vs. Parboiling: Roasting the bones led to beefier emanations. Unfortunately, that essence of beef dulled all other flavors, including the aromatics it simmered with. The broth was opaque, less fatty, but lots more scummy. Tasting it cold was pleasant enough. But heated through, it tasted monoflavored if not flat. From Day 1 to Day 3, the degradation of flavor was dramatic. As each day passed, each taste was muddier than the last.

Parboiled bones produced a fattier broth but with minimal scum. What was startling was the resulting clarity of flavor. We were able to appreciate the spices individuated and in concert. Sipped cold, the broth could pass as a refreshing beef-beverage, and heated through, the taste was just as vivid. Day 1 was enjoyable; Day 2 even more so. Even as late as Day 3, the broth held up.

More Time = More Awesome? In terms of simmering time, a 10-hour simmer did not taste appreciably better than an eight. Unfortunately, the meat suffered at the hands of extra time. Past some optimal point, the longer it stewed, the more the tail toughened. The sweet spot in time is probably somewhere between 6 to 8 hours. Also of note: fattier cuts of tail are better moisturized to survive long durations of heat.

Raw oxtails for making Vietnamese pho.
Oxtail tableau.

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Truly great dishes travel far from their origins. The changes made to them can reflect poverty, abundance, climate, even evolving attitudes. While there are many recipes out there with purists to defend them, this phở reflects my parents' own migration, from north Viet Nam to south and marries the best both have to offer. Simmered with rich oxtail and a generous amount of spice, this soup's got flavors both deep and bright.

Phở Đuôi Bò (Vietnamese Noodle Soup with Oxtail)

I like my phở broth silky with gelatin but not slick with grease, so I skim the fat pretty aggressively. To cut down on skimming efforts and to allow flavors to fully develop, I give myself a couple of days to build the broth.

Most cookbooks call for a three-hour simmer of shank bones, but an eight-hour simmer of oxtail yields a deeper, darker, more robust soup. The meat practically shudders off the bone. The trick to simmering the soup? Low + slow.

On Day 1, simmer the broth, cool, and refrigerate it overnight. On Day 2, scoop off the crust of coagulated fat and reheat the broth to serve. A lot of the broth prep is passive cooking, that is, merely keeping an eye on a barely-bubbling cauldron. In that sense, the recipe's perfect for bad rain and a good book.

Makes 8 large bowls, or 6 phở xe lửa-sized bowls (approximately 5 quarts of broth). Uneaten broth can be scooped into single-serving plastic tubs, frozen, and refreshed with ginger upon reheating.

Day 1: Broth Building

Equipment:

Stock pot (minimum capacity of 12 quarts, for cooking bones and broth) Stock pot (minimum capacity of 6 quarts, for cooking noodles) Wide skillet Cheesecloth Twine Tongs or long-handled wooden chopsticks Long-handled fine-mesh skimmer (for straining fat) Chinois or mesh strainer lined with cheesecloth (for straining scum) Long-handled large-mesh basket (for blanching noodles) 6 to 8 deep, wide-mouthed bowls for serving

Recipe Details

Phở Đuôi Bò (Vietnamese Noodle Soup with Oxtail) Recipe

Total 0 mins
Serves 6 to 8 servings

Ingredients

Spices:

  • 10 star anise

  • 10 whole cloves

  • 5 inches of cassia bark or cinnamon stick

  • 10 green cardamom pods

  • 2 teaspoons Sichuan peppercorn

  • 2 teaspoons coriander seeds

  • 2 slices of dried tangerine peel

Aromatics:

  • 1 1/2 pounds yellow onions, outer skin peeled

  • 1 pound daikon, peeled and cut into 4-inch segments

  • 1/2 pound carrots, peeled and halved

  • 4 ounces ginger, peel-on and lightly smashed

Meat and Bones:

  • 7 1/2 pounds oxtail, cut in cross-sections of roughly the same size and thickness

Broth Seasoning:

  • 2 tablespoons sea salt

  • 1/4 cup plus 2 tablespoons fish sauce

  • Yellow rock sugar, to taste

Mise en Place:

  • 1 1/2-2 pounds (1/4-inch wide) pho noodles, fresh or dried

  • 1 medium sweet yellow onion, sliced paper-thin

  • Scallions, cut into thin rings

  • Cilantro chopped

  • Oxtail meat, brought to room temperature, removed from bones, and broken into chunks

Broth Seasoning:

  • Pho broth (recipe above)

  • 2-inch knob of ginger, lightly smashed and thickly sliced

  • Fish sauce

  • Yellow rock sugar

Tableside Garnishes:

  • Spearmint

  • Thai basil (rau que)

  • Thorny cilantro (ngo gai)

  • 3/4 pound bean sprouts

  • 3-4 red Thai bird chilis, deseeded and thinly sliced

  • 2 limes, cut into wedges

  • Fish sauce

Directions

  1. Toast Spices: Toast the spices in a wide skillet over a low flame for approximately 2 minutes. Remove them from heat as they become fragrant. Cool before wrapping the spices in cheesecloth and tying off with twine.

  2. Roast Aromatics: Balance ginger knobs on the cooking grate of a gas stove. On medium-low heat, use tongs or chopsticks to char the ginger against the open flame of the stove. After 4 minutes, they should soften and brown. Do the same for the onions. These aromatics are what sweeten the broth so don't worry too much about blackening the entire surface. Allow the aromatics to cool, then peel the skins, rinse, and set aside.

  3. Parboil Meat and Bones: Place oxtail sections in the large stockpot and cover with cold water. Boil vigorously over high heat for 2 to 3 minutes. (This frees the oxtail of marrow and other impurities that cloud the flavor of the soup.) Drain and rinse the oxtail. Scrub the stockpot of scum and return the oxtail to the cleaned pot.

  4. Prepare Broth with Oxtail:

  5. In the oxtail stockpot, add 7 1/2 quarts of cold water along with the spice sachet, onions, ginger, daikon, carrots, sea salt, and fish sauce. Over high heat, bring the ingredients to a boil.

  6. Reduce the flame, and keep the broth bubbling lightly at the lowest possible simmer. Simmer for 7 to 8 hours until the meat is deeply aromatic and shrugs off the bone in hunks.

  7. Remove the oxtail and submerge them in a clean pot of cold water for approximately 10 minutes. (This prevents the meat from drying out as it cools.) Drain the sections and bring them to room temperature. Then, secure them in plastic and refrigerate.

  8. Discard all remaining solids, aromatics, and the spice sachet. Use a chinois or a fine strainer double-lined with cheesecloth to strain the broth into a second, clean stockpot. Cool the pot of broth in a sink of cold water, then store in the refrigerator overnight to allow the flavors to develop. The fat will separate to the top and the gelatin-rich broth will congeal.

  9. Day 2: Bowl Assembly To ensure the spring of the noodles don't get sodden in the broth, arrange the dry ingredients (noodles, onions, and oxtail meat) in bowls and seat guests before ladling on the liquid. Guests will enjoy plunging through the heady steam as the soup is slurped.

  10. Tableside Garnishes: Rinse, drain, spin (or pat) dry the final garnishes before arranging on a plate.

  11. Mise en Place: If using dry pho noodles, submerge the noodles in hot water for 20 minutes until softened; drain. (If using fresh noodles, simply rinse the noodles under cold water and drain.)

  12. In a clean stockpot, bring 4 quarts of water to a boil. Place the noodles in a long-handled strainer and blanch just until the noodles lose their stiffness. (Depending on the noodle and its thickness, this can take anywhere between 10 seconds to 2 minutes.) Drain.

  13. Fill each serving bowl a quarter of the way up with noodles. Top with oxtail meat, onions, scallions, and cilantro.

  14. Broth Seasoning: Remove the stockpot of broth from the refrigerator. Scoop off the white crust of fat but reserve some for flavor. Place the pot of gelatinous broth on heat. The broth will liquefy as it's brought to a rolling boil.

  15. Refresh the flavor of the broth by adding ginger slices. Adjust the flavor of the broth with fish sauce and yellow rock sugar. (If the broth tastes a little strong, don't worry. The noodles and herbal garnishes will temper the flavor.)

  16. Serving Guests: Ladle the broth into each prepared bowl and fully submerge the noodles. (The proportion of broth to noodles should be roughly 3:1.) Serve immediately. Invite guests to hand-shred tableside garnishes into their bowls and to add lime, fish sauce, and/or chili pepper to taste.

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Nutrition Facts (per serving)
703Calories
23gFat
88gCarbs
36gProtein
×
Nutrition Facts
Servings: 6 to 8
Amount per serving
Calories703
% Daily Value*
Total Fat 23g29%
Saturated Fat 10g49%
Cholesterol 94mg31%
Sodium 2206mg96%
Total Carbohydrate 88g32%
Dietary Fiber 6g23%
Total Sugars 8g
Protein 36g
Vitamin C 18mg90%
Calcium 134mg10%
Iron 5mg30%
Potassium 835mg18%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

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