In the mood for a comforting bowl of hot noodle soup? Make this one-pot Easy Udon Noodle Soup in just 10 minutes! With a light, savory broth and thick and chewy Japanese noodles, this recipe hits the spot every time.
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This 10-Minute Udon Noodle Soup recipe is at the top of my son’s list for our Easy College Meal Series. He loves that it’s simple, nutritious, and filling. It really hits the spot when he wants a piping-hot bowl of homey comfort! I’ll show you how to make this classic Japanese meal in no time and customize it with your favorite toppings.
Craving more easy Japanese noodle soups? Try my popular Soba Noodle Soup, Nabeyaki Udon, and Beef Udon recipes!
Table of Contents
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Why I Love This Recipe
- Cooks in just one pot! There’s no need to boil the noodles in a separate pot with this quick method. I love the minimal equipment and clean up!
- A go-to comfort dish any time of year. Who can resist the hot savory soup and chewy, thick noodles? Without a doubt, it is soul food that will warm you from the inside out.
- Absolutely foolproof and beginner-friendly! This recipe proves that you can cook a delicious and affordable Japanese meal yourself, even if you’re in a tiny dorm room.
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Ingredients for Easy Udon Noodle Soup
- frozen udon noodles – I use thick and chewy frozen Sanuki udon
- Japanese noodle soup base (mentsuyu) and water – for the soup broth
- Shanghai bok choy or any greens
- soft or hard-boiled egg
- fried fish cake (satsumaage) – optional
- kamaboko (fish cake) – optional
- shichimi togarashi (Japanese seven spice) – optional
What is Mentsuyu?
Mentsuyu (めんつゆ) or tsuyu is a Japanese soup base used to flavor noodle soups, rice bowls, hot pots, and tempura dipping sauces. It’s made from sake, mirin, soy sauce, and kombu and katsuo (dried bonito flakes) dashi. The flavor is both delicate and intensely savory. Typically sold in concentrated form, you can easily dilute it with water for use.
Find the printable recipe with measurements below.
Jump to RecipeSubstitutions
- Shanghai bok choy – You can use green cabbage, napa cabbage, or other leafy greens like spinach in place of the bok choy.
- Frozen udon noodles – If you don’t have frozen udon, simply add in pre-cooked noodles at the end of cooking.
- Mentsuyu – If you can’t find bottled Japanese soup base, you can make soup broth from scratch with a mixture of dashi (Japanese soup stock), soy sauce, and mirin instead.
How to Make Easy Udon Noodle Soup
Preparation
Step 1 – Cut the Shanghai bok choy. You’ll need half a head cut into two quarters. I like to slice through the bottom white part first, then use my hands to tear apart the two pieces.
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Cooking
Step 2 – Boil the soup broth and cook the bok choy. Heat the mentsuyu (soup base) and water until boiling, then add the bok choy and cook for 45 seconds.
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Step 3 – Heat the frozen udon and fried fish cakes. The brand of frozen udon I use requires just 1 minute to reheat from frozen. Stir with chopsticks to loosen up the noodles in the boiling broth.
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Step 4 – Serve! Transfer everything to a large bowl and arrange the bok choy, fried fish cakes, kamaboko slices, and boiled egg on top. Sprinkle with optional shichimi togarashi and enjoy!
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Nami’s Recipe Tips
- Use frozen udon noodles – I recommend using pre-cooked frozen udon noodles, which will give you the best texture. I like using thick and chewy frozen Sanuki udon from a Japanese market. There’s no need to defrost them, as they reheat in the boiling broth in just 1 minute.
- Use bottled noodle soup base – For this quick method, I use convenient mentsuyu that comes in a bottle. If you have time, you can make the soup broth from scratch as I do in my original Udon Noodle Soup recipe.
Variations and Customizations
- Change up the toppings. You can use any toppings you like. Try deep-fried tofu pouches (aburaage), baked tofu, shiitake mushrooms, wakame seaweed, or store-bought tempura. You could also keep it simple with just sliced green onions!
- Use other noodles. You can use rice noodles or 100% buckwheat noodles (juwari soba) for gluten-free, and konnyaku noodles for a low-calorie option.
- Vegan/vegetarian versions. Standard store-bought bottles of mentsuyu from Japanese and Asian markets are not vegan/vegetarian friendly. Therefore, I encourage you to make your own mentsuyu at home. The good news is it’s super easy. First, make the Kombu Dashi or Vegan Dashi (both take just 20 minutes), and add sake, mirin, and soy sauce to the dashi. It’s as easy as going to the store!
What to Serve with Udon Noodle Soup
This udon noodle soup is easily a meal in itself, but it also pairs wonderfully with:
- Yakitori – Serve the grilled chicken as an appetizer or savory bite.
- Japanese Cucumber Salad – A refreshing crunchy cucumber salad as a palate cleanser.
- Salmon and Shio Kombu Onigiri – Additional carbs for a big eater!
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Storage and Reheating Tips
To store: You can keep the udon noodles and broth separately in airtight containers and store them in the refrigerator for up to 3 days. However, it’s best to prepare the udon noodles right before you assemble and serve. I don’t recommend freezing the leftovers.
Frequently Asked Questions
We found that adding the frozen udon noodles directly into the broth doesn’t cloud the soup too much, and the result is satisfactory enough that you can skip an extra step here. These udon noodles are already pre-cooked, so you have to heat them up for one minute.
More 10-Minute Recipes
If you love this Easy Udon Noodle Soup, check out some of my other 10-Minute College Meals:
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10 Minute Meal – Udon Noodle Soup
Video
Ingredients
- ½ head Shanghai bok choy (you can substitute with napa cabbage, green cabbage, or spinach)
- 1½ cups water
- ¼ cup mentsuyu (concentrated noodle soup base) (if you can't buy a bottled soup base or need a vegan/vegetarian version, make my Homemade Mentsuyu recipe)
- 1 serving udon noodles (frozen, about ½ lb/250 g per serving; I like to use frozen Sanuki udon from Asian/Japanese markets)
- 2 pieces satsumaage (fried fish cakes) (optional)
- 2 slices kamaboko (fish cake) (optional)
- 1 soft or hard-boiled egg (sliced in half)
- shichimi togarashi (Japanese seven spice) (optional, for a spicy kick)
Instructions
- Gather all the ingredients. I use an electric pot for this recipe and others in the 10-Minute Meal series. You also could use a regular saucepan on the stove.
- Trim the stem end of a head of Shanghai bok choy and cut it in half lengthwise. I slice through the bottom white part with my knife, then pull apart the two halves with my hands. Cut ½ head Shanghai bok choy in half again so you have two quarters. Reserve the rest of the bok choy for another use.
To Cook the Udon Noodle Soup
- Add 1½ cups water and ¼ cup mentsuyu (concentrated noodle soup base) to a saucepan or electric pot. Cover with a lid. Heat the saucepan over medium-high heat or on Mode II (600W) for the electric pot.
- When the broth is boiling, add the bok choy. Cover the pot and cook for about 45 seconds, depending on the bok choy's size.
- Next, add 1 serving udon noodles (no need to defrost) to the boiling soup broth. Add 2 pieces satsumaage (fried fish cakes) on top of the frozen noodles. Cook the noodles according to the package instructions. This brand of frozen udon noodles requires reheating for 1 minute. Using chopsticks, stir the noodles to loosen them up.
To Serve
- Transfer the noodles and soup broth to a large bowl and arrange the bok choy and fried fish cakes on top. Add 2 slices kamaboko (fish cake) and 1 soft or hard-boiled egg.
- If you'd like, sprinkle shichimi togarashi (Japanese seven spice) on top for a spicy kick. Enjoy!