Kitsune Udon (Japanese Udon with Sweet Simmered Tofu)

Kitsune udon (きつねうどん) — udon noodles in a clear, golden dashi broth, topped with a sweet simmered tofu pouch — is one of the most loved noodle dishes in Japan. It’s especially popular in Kansai (Osaka and Kyoto), where the broth is light and lets the dashi do all the talking. The name means “fox udon,” because the deep-fried tofu is supposedly a fox’s favourite food in Japanese folklore.

This is the version I make at home with two shortcuts: a dashi packet for the broth (no need to make dashi from scratch), and frozen udon noodles that go straight from freezer to microwave in 4 minutes. Total time from cold start to a bowl on the table: about 10 minutes.

Why You’ll Love This Recipe

• 10 minutes from start to finish if you have the simmered age already made.
• Clear, light, dashi-forward broth seasoned with usukuchi (light) soy sauce and salt — Kansai-style, not the dark Kanto-style.
• Microwave-friendly frozen udon means no second pot of boiling water, no draining, no fuss.
• Real Japanese home cooking, not a restaurant version — this is exactly how I make it on a tired weeknight.

The Two Key Ingredients

1. The Sweet Simmered Tofu Pouches (Kitsune Udon No Age)

These are the star of the dish — thin fried tofu sheets (aburaage) simmered in a sweet-savoury broth until they’re golden, juicy, and bursting with flavour. Make a batch ahead and keep them in the fridge so kitsune udon becomes a near-instant meal.

👉 Full recipe here: Kitsune Udon No Age — Sweet Simmered Tofu Pouches

2. A Good Dashi Packet

The broth is what makes or breaks kitsune udon. Since the seasoning is just dashi + usukuchi soy sauce + salt, the dashi has to be flavourful on its own.

For this batch I used an ago-uma dashi pack from Nagata Foods in Nagasaki — ago (flying fish) dashi has a deep, slightly smoky flavour that’s particularly good with udon broth. Any good Japanese dashi packet works though — bonito (katsuobushi), kombu, or a blend. If you want a primer on choosing dashi packets, see my dashi packets guide.

👉 Kuze Fuku Traditional Umami Dashi Packets — available on Amazon

Ingredients

Serves 2

Ingredient	Amount
Frozen udon noodles	2 portions (about 200g each)
Simmered aburaage (kitsune udon no age)	2 pieces
Water	500ml
Dashi packet	1 packet (8–10g)
Usukuchi (light) soy sauce	2 tbsp, plus more to taste
Salt	A pinch, to taste
Green onion, finely sliced	To garnish

A Note on Usukuchi (Light) Soy Sauce

Kitsune udon is famously a Kansai dish, and the broth uses usukuchi shoyu (薄口醤油) — light-coloured soy sauce. Don’t be fooled by the name: usukuchi is actually saltier than regular (koikuchi) soy sauce. It’s lighter in colour, which keeps the broth golden rather than brown, but stronger in salinity.

If you can’t find usukuchi shoyu, you can use regular soy sauce — just use a little less (start with 1.5 tbsp instead of 2), and the broth will be darker than the classic Kansai look. Still delicious.

👉 Japanese Usukuchi (Light) Soy Sauce — available on Amazon

A Note on Frozen Udon

Frozen udon noodles (冷凍うどん) are one of the most underrated freezer staples in Japanese cooking. They go from freezer to bowl in 4 minutes in the microwave, with a chewy, springy texture that’s almost as good as fresh-made. Most major Japanese grocery stores carry them; look for individually-packed portions labelled “Sanuki udon” (讃岐うどん) — that’s the thick Kagawa-style udon you want for kitsune udon.

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How to Make Kitsune Udon

Step 1: Make the Dashi

Add 500ml of water and 1 dashi packet to a small pot. Bring to a boil over medium heat, then reduce the heat and simmer for 3–5 minutes. The water will turn a clear golden colour as the dashi steeps. Remove and discard the dashi packet.

Step 2: Season the Broth

Add 2 tablespoons of usukuchi soy sauce to the dashi. Stir, then taste. Add a small pinch of salt if you want a touch more savouriness, or another splash of soy sauce if you want it bolder. The broth should taste light, clean, and dashi-forward — not too salty, but with enough depth that you’d happily drink it as a soup.

Adjust to your taste. Some people prefer it a little saltier, some lighter. The 2 tbsp + a pinch of salt ratio is my baseline.

Step 3: Heat the Udon in the Microwave

While the broth is simmering, microwave the frozen udon according to the package instructions. For my brand, it’s about 4 minutes at 500–600W per portion. The noodles should be hot all the way through and easy to separate with chopsticks.

You can also boil the udon in a separate pot of water if you don’t want to microwave — but the microwave method keeps the broth clean and saves washing up a pot.

Step 4: Warm the Simmered Age

Take the simmered aburaage (kitsune udon no age) out of the fridge and warm it gently — either in its broth in a small pan over low heat for a minute, or in the microwave for 20–30 seconds. You want it warm to the touch, not hot.

Step 5: Assemble the Bowls

Place a portion of hot udon noodles into each bowl. Ladle the hot dashi broth over the top, making sure it covers the noodles. Lay one warmed piece of simmered age across the top, then sprinkle generously with sliced green onion.

Serve immediately while everything is hot. Eat the noodles, the age, and the broth all together — that’s the point of kitsune udon.

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Tips for the Best Kitsune Udon

• Make the simmered age ahead. They take 10 minutes to make and keep for 3–4 days. Having them ready turns kitsune udon into a real weeknight dinner.
• Taste the broth before serving. Different dashi packets have different salt levels. The 2 tbsp + pinch of salt is a guide — your dashi might need a little more or less. Trust your tongue.
• Use usukuchi soy sauce if you can. It keeps the broth golden (the Kansai-style look) and adds the right salt level without darkening the soup.
• Frozen udon is genuinely good. If you’ve only had dried udon, frozen will surprise you. The chewy texture (called koshi) holds up much better than dried noodles.
• Don’t let the udon sit in the broth too long. They keep absorbing liquid. Serve and eat right away.

Variations

• Kitsune Soba — Use soba noodles instead of udon. The same broth and simmered age work perfectly.
• Add a poached or onsen egg — Crack one into the broth at the end and cover for a minute. The yolk enriches the soup.
• Add tempura crumbs (tenkasu) — Sprinkle on top for a richer, slightly oily texture. Very satisfying.
• Add wakame or spinach — A small handful of seaweed or blanched greens makes it feel more like a balanced meal.