If you have butter, soy sauce, and spaghetti in your pantry, you can make this mouthwatering Japanese-style pasta with a medley of mushrooms. Butter Soy Sauce Pasta is ridiculously flavorful for the small amount of effort, so this weeknight pasta is sure to become a favorite.

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If you have butter, soy sauce, and spaghetti in your pantry, you can make this mouthwatering Japanese pasta.

Butter Soy Sauce Pasta

When melted butter and soy sauce are whisked together, it forms a creamy emulsion that's intensely savory. This forms a popular sauce that's used on everything from chicken to rice to potatoes to mochi in Japan.

Pasta is another great way to enjoy this sauce, and Butter Shoyu Pasta (バター醤油パスタ) is a ridiculously easy dish that can be thrown together from just three ingredients, making it the second most popular pasta in Japan. The most common combination is to add a mix of Japanese mushrooms, but it can be prepared with almost any protein or vegetable.

What is Wafu Pasta?

Wafu Pasta (和風パスタ) literally means "Japanese-style pasta." Although Western-style pasta has been around in Japan for nearly 100 years, it wasn't until a boom in Italian cuisine during the 1980s that it became widespread in Japanese homes.

With the rising popularity of pasta, creative cooks started incorporating ingredients from the Japanese pantry to make it more accessible. By the 1990s, there was a raft of new pasta dishes such as Mentaiko Pasta and this Butter Shoyu Pasta.

Japanese mushroom pasta with butter and soy sauce.

Ingredients for Butter Soy Sauce Pasta

Butter - I like using cultured unsalted butter for this because the fermentation process produces more diacetyl than regular sweet butter. This compound is what's responsible for making butter taste buttery, so cultured butter is significantly more flavorful than regular butter. Also, by using unsalted butter, it allows you to add more soy sauce without making the pasta salty. If your butter is salted, be sure to reduce the amount of soy sauce you add.
Soy Sauce - I'm using ordinary Kikkoman soy sauce for this, but any Japanese-style soy sauce will work. If you use usukuchi soy sauce, be sure to reduce the amount of soy sauce, as this variety contains a higher concentration of salt.
Pasta - The most common pasta used in Japan is spaghetti; however this works with any shape of pasta.
Aromatics - I've added garlic to this one because it goes with the mushrooms, but this is totally optional. You can also add other aromatics like onions, ginger, or scallions here.
Mushrooms - I've used equal parts Shiitake, Maitake (Hen of the Woods), and Shimeji (Beech) mushrooms for this, but any mushroom you have on hand, such as Button, Crimini, or Oyster mushrooms will work as well.
Vegetables - I prefer having my veggies separately (this pasta goes great with a salad), but some people like to add vegetables such as corn, potatoes, asparagus, or spinach to this dish.

Spaghetti tossed with butter, soy sauce, and mushrooms is a classic Japanese pasta recipe.

How to Make Japanese Butter Shoyu Pasta

The first thing you want to do is bring a wide pot filled with about 2-inches of well-salted water to a boil. Contrary to common wisdom, for pasta dishes that use the boiling water, you want to use as little water as possible so that the water becomes nice and starchy. This is what helps you emulsify the butter and soy sauce together into a smooth sauce.

While you are waiting for the pasta water to boil, clean all of the mushrooms, trim off any inedible parts, and then slice or shred them into bite-sized pieces. Mince up the garlic and parsley.

Once the water is boiling, add the pasta and quickly submerge it under the water. You will want to stir the pasta regularly for the first minute or two to keep it from sticking together.

Add the olive oil to a frying pan over medium-high heat and saute the garlic until it is very fragrant, but not yet brown.

Add the mushrooms to the pan, sautee them until they have wilted, and started to brown.

When the pasta is nearly done, add the butter to the mushrooms and melt it.

Add the soy sauce and a ladleful of the boiling liquid from the pasta and stir vigorously to emulsify the mixture with the butter.

When the pasta is done, transfer it to the pan with the mushrooms. Toss everything together until the spaghetti is evenly coated with the sauce. You can add more pasta water as needed to keep the pasta from sticking.

Garnish with the chopped parsley and serve immediately.

Variations of Butter Shoyu Pasta

The only necessary ingredients in this recipe are butter, soy sauce, and pasta, so there's a lot of flexibility in terms of what you can add to this. Here are a few ideas to get you started:

Edamame and Bacon - This is a colorful and delicious combination, but if you do use bacon (or any cured meat), you will want to reduce the amount of soy sauce a little as bacon is quite salty.
Scallop with Butter Soy Sauce - Any seafood, including crab, shrimp, and clams, make for a delicious butter shoyu pasta, but my absolute favorite is scallops. Just coat the scallops in a little oil, and get your frying pan scorching hot. Sear both sides of the scallops and then glaze them with half of the butter and soy sauce. Remove them from the pan while you wait for the pasta to finish. Then you can make an emulsion with the remaining soy sauce and butter along with some pasta water and then toss the pasta and scallops together in the sauce.
Sous Vide Egg - Make your favorite version of butter shoyu pasta and then top it with a sous vide egg (or poached egg, or sunny side up egg).

Other Japanese Pasta Recipes

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