Featured Comment
Really enjoyed this recipe. The big thing for me was the contrast between the light broth and the rich marinated pork belly. Will be adding this into our family menu rotation.
★★★★★
– Carolyn Brodersen
The dashi broth is pale, almost transparent, and its aroma greets you as you lean over the bowl. With the first slurp, you taste the savory pork belly fat that has melted into the broth and coated the udon.
For all that depth of flavor, this pork udon eats light. That’s the bowl this recipe makes.
Pork Udon
Recipe Snapshot
- What is it? This home-style pork udon pairs noodles in pale dashi broth with pork belly and onion fried in their marinade. The pan juices go into the bowl too.
- Flavor profile: Dashi is the first thing you smell. A mouthful brings the sweet, savory pork fat, sweet-salty marinade and tender onion, then a sharper finish if you add shichimi.
- Why this recipe works: The lightly seasoned broth gets its full flavor from the pan juices when you assemble the bowl. You use all the marinade, while usukuchi keeps the broth pale.
- How to make it: Marinate pork in usukuchi and dashi. Boil dashi and mirin, then add soy sauce off the heat. Fry salted onion, then the pork in its marinade, and spoon over udon.
- What to expect: Allow about 25 minutes, 15 for prep and 10 for cooking. The broth alone tastes weak, so resist adding soy sauce. Stir in the pan juices before judging the seasoning.
What Is Pork Udon?
Butaniku udon (豚肉うどん), or pork udon, is a hot Japanese noodle dish with a sweet-salty pork topping. It’s one kind of niku udon, meaning “meat udon,” which can feature either beef or pork in Japan. Pork is a standard choice in its own right, never a stand-in for beef.
Around Osaka and Kyoto, in the Kansai region, “meat” means beef, and that’s what you get in niku udon. A steamed pork bun there is even called butaman, “pork bun,” rather than nikuman, “meat bun.” Pork udon is nevertheless an everyday meal in home kitchens.
Usukuchi (薄口) is a light-colored Japanese soy sauce particularly common in Kansai cooking. It seasons dishes without darkening them, preserving the dashi’s color and aroma. Here, “light” refers only to color and has nothing to do with salt. In fact, usukuchi is saltier than koikuchi (濃口), the standard Japanese soy sauce. One manufacturer’s labels list 2.8 g of salt per tablespoon of usukuchi, compared with 2.5 g for koikuchi. Don’t let that pale color tempt you to add too much, or your soup may end up overly salty. Chinese light soy sauce is a separate product.
Pork Belly Udon Ingredients
- Thinly sliced pork belly: Look for slices about 2 mm thick (roughly 1/16 inch), the sort stocked in every Japanese supermarket. For US shoppers, pork belly labeled for shabu-shabu or hot pot is the cut to seek out. An Asian grocery store is the most reliable place to find it, sometimes with 1.2 mm or 2 mm printed on the package. Korean barbecue pork belly, known as samgyeopsal or the KBBQ cut, is usually 6 to 10 mm thick, a bit too thick here. If all you can find is a slab, chill it in the freezer for 1 to 2 hours, just until firm but not frozen solid, before cutting thin slices yourself. Another option is to have the butcher slice it.
- Dashi (kombu and bonito): With only usukuchi (light-colored) soy sauce and mirin to season the broth, the flavor of your dashi has nowhere to hide. Choose the tastiest dashi you can find. Kombu is kelp, and bonito flakes are dried fish flakes. The better the dashi, the less salt it needs, and in this recipe that salt comes from soy sauce.
- Udon: Frozen, dried, fresh or homemade udon, choose whichever is easiest for you.
Substitution Ideas
- Thinly sliced pork belly → thinly sliced pork shoulder: A leaner cut, shoulder releases less fat into the broth for a lighter bowl. If you can only buy a slab, have the butcher slice it thinly. A reader who tried sliced shoulder reported that the whole family enjoyed it.
- Usukuchi soy sauce → standard Japanese soy sauce: The same quantity works here. Expect a darker broth and marinade, both a little less salty.
- Kombu and bonito dashi → dashi granules or dashi packs: Watch the seasoning, as some granules already contain salt and other seasonings. Granules contribute roughly 0.25 g of salt per 100 ml of dashi, making the broth a little saltier before assembly. Wait until you’ve added the pan juices to taste it.
- Shichimi togarashi (Japanese 7-spice chili blend) → leave it out: This is an optional finishing sprinkle, so there’s no need for a replacement if you don’t have any.
- Kamaboko (Japanese fish cake) → leave it out: You can serve the soup without it. In Japan, some bowls of pork udon have only green onions as a garnish.
Substitutions that I don’t recommend:
- Chinese dark soy sauce instead of usukuchi soy sauce: Its thickness and sweetness are too much for this broth.
- US chili powder instead of shichimi togarashi: Although both contain a mixture of spices, the chili powder sold in US spice jars is often ground dried chiles with garlic, cumin and oregano, a different blend from shichimi.
For other Japanese pantry staples you can’t find, my guide to Japanese ingredient substitutes has more swaps.
How to Make My Pork Udon Soup
Before you start (Mise en place):
- Prepare the dashi for both the marinade and broth together.
- In a container, combine the sliced pork belly with usukuchi soy sauce, mirin, sugar, tube ginger and dashi. Mix, then refrigerate for 10 to 30 minutes to marinate.
- Slice the onion into thin wedges. In a separate bowl, toss the wedges thoroughly with salt and set aside until you’re ready to fry them. Salting draws out moisture and some of the onion’s sharpness, and frying then brings out its sweetness.
i. As the pork marinates, heat the dashi and mirin in a pot over medium heat. Bring to a boil and let it bubble briefly to cook off the alcohol in the mirin.
ii. Switch off the heat before stirring in the usukuchi soy sauce. Put the lid on and leave the pot on the stove to keep warm.
Prolonged simmering diminishes soy sauce’s aroma. That’s why you add it at the end and don’t boil the broth again.
iii. For dried udon, get a separate pot of water boiling. Use the package cooking time to work backward, starting the noodles before you begin frying the onion.
Homemade dashi might sound like extra work. In my experience, with a little care and some planning ahead, it takes almost no extra time or effort.
At this stage, I deliberately leave the broth lightly seasoned. The juices from the frying pan will complete it when you put the bowls together. If you taste it now, it will seem a little flat, but don’t add more soy sauce. Wait to taste again until you’ve mixed everything together at the end.
i. Set a frying pan over medium heat and add the oil and salted onion. Fry until softened and lightly colored.
Look for translucent edges and a few pale golden patches before continuing.
ii. Tip in the pork and all its marinade, and fry with the onion. Keep the rendered pork fat in the pan.
iii. Switch off the heat once the pork has changed color and browned a little, with juices still remaining in the pan.
You will need that liquid to finish the broth, so don’t let it evaporate completely.
i. While the pork cooks, heat frozen or precooked udon in a separate pot until the noodles have loosened and are hot throughout. Follow the package instructions for dried udon.
I find that cooking the pork and noodles at the same time depends less on skill than on thinking through the sequence before you start.
ii. Spoon some of the noodle cooking water into the serving bowls to warm them. This helps the broth hold its heat for longer.
iii. Drain the noodles, then rinse them with fresh boiling water to wash away the slippery coating.
i. Reheat the broth until it is just short of boiling. If you’re adding kamaboko, place the slices in the broth for 20 to 30 seconds to warm through.
ii. Empty the warming water from the bowls. Divide the udon between them, 1 portion per bowl, or half the cooked noodles each if using dried udon. Add the broth.
iii. Arrange the pork and onion on top. Divide all the remaining pan juices, including the fat, equally between the 2 bowls. Add 2 slices of kamaboko to each bowl if using, followed by chopped green onions and an optional sprinkle of shichimi.
iv. Stir thoroughly before eating.
Tips for the Best Japanese Pork Udon
- Save the pan juices before they evaporate. Their flavor completes the lightly seasoned broth when you assemble the bowls. As soon as the pan dries out, the marinade’s sugar and mirin begin to brown. Once the juices turn glossy, stay right at the stove and turn off the heat before black, sticky patches or a bitter smell develop.
- Cook the onion and pork in 2 batches for a double recipe. Twice the pork and marinade in one pan will steam rather than brown. Moisture released by the onion also dilutes the pan juices. You can still make all the broth in one pot, which comfortably accommodates double the amount.
- Dissolve the sugar as you mix the marinade, then leave the pork to marinate. Since all that marinade goes into the pan with the pork, any undissolved sugar can easily scorch. Some Japanese cooks who live abroad also find that locally available sugar doesn’t suit the Japanese dishes they make.
Carry every drop of those pan juices to the bowl, give it a good stir, and that pale broth turns into this pork udon.
Storage & Meal Prep
Fridge: Pork, onion and juices keep 2 days. Cooled broth, covered separately, keeps 2 to 3. Don’t store udon in broth, where it swells.
Freezer: Bag pork and onion with juices, 2 to 4 weeks. Freeze dashi unseasoned, since freezing dulls soy sauce and mirin.
Meal prep: Portion a double batch with juices.
Reheating: Fridge-thaw pork overnight, then pan-warm it with its juices over medium heat. Reheat broth without boiling.
What to Serve With Pork Udon
- Crispy Vegetable Kakiage
- Takikomi Gohan (Seasoned Rice with Chicken)
- Kinpira Gobo (Braised Burdock)
- Quick Napa Cabbage Pickles (Hakusai no Asazuke)
Butaniku Udon Troubleshooting
If the entire broth tastes salty, rather than just the pork, your dashi probably contained salt already. Salted granules or dashi packs make the broth a little saltier even before you add the pan juices. Stir in small amounts of unsalted dashi or hot water, tasting as you go.
Well-seasoned pork with bland broth is a sign that the pan juices haven’t reached the bowl. Add everything left in the frying pan, including the fat, and stir well again. If the liquid has evaporated entirely, mix the soup first, then adjust it with a little usukuchi soy sauce at a time until you’re happy with the flavor.
When pale pork sits bubbling in a puddle, either the slices are crowded together or the heat is too low. Arrange them without overlapping and keep the burner at medium. They won’t brown until the liquid has reduced. Once they do, turn off the heat while a little juice still remains at the bottom of the pan.
More Japanese Udon Recipes
After pork, trade the topping for fried tofu, chicken or egg over the same dashi broth, and find your next bowl in my Japanese Udon Recipes.
Did You Try This Recipe?
I would love to hear your thoughts!
💬 Leave a review and ⭐️ rating in the comments below. 📷 I also love to see your photos – submit them here!
Pork Udon Noodle Soup (Butaniku Udon)
Ingredients
Marinated Pork
- 150 g thinly sliced pork belly about 2 mm thick, the kind sold for shabu-shabu
- 2 tsp Japanese light soy sauce (usukuchi shoyu) Japanese usukuchi, a different product from Chinese light soy sauce
- 1 tbsp mirin
- ½ tsp sugar
- ½ tsp grated ginger root or a tube
- 3 tbsp dashi stock
Broth
- 500 ml dashi stock
- 1 tbsp mirin
- 1 tbsp Japanese light soy sauce (usukuchi shoyu)
To Finish
- 1 tsp cooking oil
- 2 portions udon noodles frozen, dried, fresh or any kind, about 200 g per portion, or 80 to 100 g dried per serving
- 4 slices kamaboko fish cake optional
- finely chopped green onions about 1½ tbsp per bowl, optional
- Japanese chili powder (shichimi togarashi) optional
The ingredient brands and tools I trust are in my Japanese pantry guide and my cooking tools guide.
Can’t find certain Japanese ingredients? See my substitution guide here.
Instructions
Prep the Pork and Onion
- Put 150 g thinly sliced pork belly in a container and add 2 tsp Japanese light soy sauce (usukuchi shoyu), 1 tbsp mirin, ½ tsp sugar, ½ tsp grated ginger root and 3 tbsp dashi stock. Stir until the sugar dissolves, then marinate in the fridge for 10 to 30 minutes. While the pork marinates, toss 50 g onion (cut into thin wedges) with ⅛ tsp salt in a separate bowl until every piece is coated. Leave it there until you fry it.
Make the Broth
- Pour 500 ml dashi stock and 1 tbsp mirin into a pot and set it over medium heat. Bring it to a boil, boil briefly and turn off the heat.
- Stir in 1 tbsp Japanese light soy sauce (usukuchi shoyu), cover, and leave the pot on the stove to keep warm.
Fry the Pork and Cook the Udon
- Heat a frying pan over medium heat and add 1 tsp cooking oil and the salted onion. Fry until the onion is soft, the edges look translucent and a few spots turn pale golden.
- Add the pork with all of its marinade and fry it with the onion. Leave the rendered fat in the pan. Turn off the heat once the pork has changed color and browned lightly, while there are still juices in the pan.
- While the pork fries, cook 2 portions udon noodles in another pot until they loosen and are hot all the way through. Cook dried udon as the package directs.
- Drain the udon and pour fresh boiling water over the noodles to rinse off the slippery surface.
Assemble the Bowls
- Reheat the broth until it is just below a boil. If you are using 4 slices kamaboko fish cake, warm them in the broth for 20 to 30 seconds.
- Put 1 portion of udon in each bowl, or split cooked dried udon evenly among them, and pour in the broth. Pile the pork and onion on top and pour the pan juices, fat and all, evenly over the bowls. If you are using the kamaboko, add 2 slices to each bowl.
- Scatter finely chopped green onions among the bowls and sprinkle on Japanese chili powder (shichimi togarashi) if you like. Stir well before eating. Enjoy!
Subarashikata! Really enjoyed this recipe. I did take a few liberties–subbing chopped up raw bacon for the pork belly and adding in raw spinach and snow peas to beef up the veg quotient. The big thing for me was the contrast between the light broth and the rich marinated pork belly. Fabulish! Will be adding this into our family menu rotation.
Hi Carolyn,
Thank you so much! I love hearing how you made it your own! I’m so glad the flavor balance hit the spot. Makes me happy to know it’s earned a spot in your rotation! 🙂
Yuto
I made it with thinly sliced pork shoulder. The family appreciated the various flavors and textures that came together in this dish. I would urge everyone to not skip the shichimi togarashi. The gentle spiciness further expands and enhances the palette of contrasting flavors. Thanks, Omura.
Hi Gerald,
Thank you so much for making my pork udon recipe! I’m really glad your family enjoyed all the flavors and textures. And I agree, the shichimi togarashi adds such a nice lift to the dish! 🙂
Yuto