Ketchup in spaghetti?! You hear it right. The idea of spaghetti with ketchup sauce may make any Italian cringe. However, Japanese Ketchup Spaghetti, or what we call Spaghetti Napolitan (スパゲッティーナポリタン), has been a popular menu at cafe restaurants (Kissaten) since the 1950s. This comforting pasta dish always brings a nostalgic memory to many Japanese who grew up eating it.

What is Napolitan?

Napolitan is tomato ketchup-based, Japanese-style pasta that consists of spaghetti noodles, onions, green bell peppers, button mushrooms, and Japanese sausages. There are a few variations where we replace the sausages with bacon or ham. However, in general, it all has a standard sunny look of appetizing orange. Phonetically, the Japanese language doesn’t distinguish R and L as separate sounds. For that reason, it uses the same katakana characters to represent R and L sounds of Western alphabets. So we write it as either Napolitan or Naporitan. While the spelling “Naporitan” is derived from romanji (the romanization of Japanese), the spelling “Napolitan” takes the origin of the name (Napoli) into account.

The Origin of Napolitan

There are a few theories of how Napolitan originated. The strongest theory is that it originated in Yokohama during the postwar era. Around the 1950s, the head chef at the New Grand Hotel in Yokohama created this recipe after being inspired by the spaghetti and tomato sauce dish served to the American military. Since tomato sauce was a rare ingredient at that time, he used ketchup as a substitute for pasta sauce. He then named it “Spaghetti Napolitan”, or Napoli, after Naples, Italy. Around the same time, Japan started to open itself to the world and began to consider fashionable new ideas from the West. These newly Westernized dishes like Spaghetti Meat Sauce and Spaghetti Napolitan received excellent responses. Eventually, they became mainstays in the cafes and Japanese home kitchens. To this day, the two dishes are still two of the most popular pasta dishes among Yoshoku (Western-influenced food, 洋食) in Japan.

Ketchup as The Key Flavoring

Not surprisingly, Japanese cuisine has used ketchup in seasoning various dishes, as this all-star American condiment lends a depth of flavor with its sweet-tangy profile. Therefore, you can find ketchup used in Japanese Curry, Omurice, Ebi Chili, and a pasta dish like Spaghetti Napolitan. It’s a great example of how open we are when it comes to adapting other cultural influences in improving our own cuisine.

Why You’ll Love This Pasta

The genius about Spaghetti Napolitan is that it utilizes most of the pantry staples in your kitchen. The common ingredients include onion, mushrooms, green bell peppers, and sausages (ham or bacon). It’s seasoned with ketchup and Parmesan cheese and served with Tabasco sauce.  It’s really flexible, too! For example, you can try bacon in place of sausage. Likewise, use peas in place of bell peppers. Top it with a fried egg if you’d like. But simplicity is good for this recipe. When you don’t have any of the ingredients in the recipe, you can throw in whatever happens to be in season or on-hand in your kitchen. To make it vegetarian-friendly, leave out the meat and add more mushrooms. Mix it up with a different type of mushroom for texture and flavor. This dish is really easy to make and the flavor is kids-friendly. It makes an ideal meal for a quick dinner if you have a family with young children. I remember my son used to request this Ketchup Spaghetti when I asked what kind of pasta he would like for lunch.

Cooking Tips

Timing is key for a smooth workflow. Get your prep work done while you boil the water to cook the spaghetti. You should have the cooked ingredients and sauce ready by the time the spaghetti is done cooking. Then toss everything together and serve! The taste of ketchup slightly varies depending on the brand. I usually use this organic ketchup (No GMO ingredients, no high-fructose corn syrup) but a similar one would work great. Napolitan does have a slightly sweet taste to it, but feel free to omit the sugar as listed in the recipe. For the authentic flavor, get a bottle of Kagome Tomato Ketchup from the Japanese grocery store. It is the classic Japanese ketchup to make Omurice and Napolitan. Always reserve the pasta cooking water. Set aside ¼ cup (or more depending on the serving portion) of the pasta cooking water. The starch in this salty pasta water acts as a binder and creates an emulsion when you add it to a sauce that contains fat like butter or oil. Don’t overcook the spaghetti as you will continue to cook a bit more in the frying pan. Consider textures. In my opinion, this pasta dish tastes best with various textures. For veggies such as bell peppers or fresh peas or sugar snap pea, I’d keep them on the crunchy side. However, my kids do not like raw or undercooked bell peppers so they always ask them to be as thin and wilted as possible. I personally like to cook the onion a bit more (no need to caramelize) to get the sweet flavor out of it. Just a tablespoon of butter at the end adds umami and creaminess to the dish. So don’t skip it!

It cannot be easier to put this Spaghetti Napolitan together! For a fancy yet effortless weeknight dinner, serve it with a green salad and wine. Enjoy!

Other Japanese-Style Pasta Recipes

Miso Butter Pasta with Tuna and Cabbage Creamy Mushroom and Bacon Pasta Ume Shiso Pasta Japanese-style Pasta with Shrimp and Broccolini

Wish to learn more about Japanese cooking? Sign up for our free newsletter to receive cooking tips & recipe updates! And stay in touch with me on Facebook, Pinterest, YouTube, and Instagram. Editor’s Note: This post was originally published on Apr 19, 2013. The post has been republished with updated content, new images, and a slightly-revised recipe on July 25, 2022.

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