Have you ever tried “Napolitan” (Japanese Ketchup Spaghetti)?
Despite its name, Napolitan is a uniquely Japanese pasta dish — not Italian! It was created in the 1940s by a Japanese chef named Shigetada Irie, who was working at the New Grand Hotel in Yokohama.
After World War II, he was inspired by the simple spaghetti meals made by the American military, who used ketchup as a substitute for tomato sauce. Chef Irie adapted the idea and created a dish using spaghetti, ketchup, onions, green peppers, and sausages. He named it “Napolitan” after Naples (Napoli) to give it an Italian-sounding name.
Today, Napolitan is a nostalgic and beloved yōshoku (Western-influenced Japanese dish), commonly found in cafes and home kitchens across Japan.

Napolitan (spaghetti)
Ingredients
- 200 g spaghetti
- 2 frankfurters
- 70 g green pepper
- 1/2 onion (100g)
- 1 tsp minced garlic
For the sauce:
- 6 tbsp ketchup
- 2 tbsp soup stock (dashi)
- 1 tbsp oyster sauce
Instructions
- Slice the onion and the green peppers into thin strips. Slice frankfurters thinly on the diagonal.
- Mix all the sauce ingredients in a bowl.
- Boil the pasta according to the package instructions. Drain then drizzle 1 tbsp olive oil over it and mix gently to keep it from sticking.
- Heat 1 tbsp olive oil and minced garlic in a frying pan over a medium heat until fragrant, then saute the onions for 2 minutes followed by the frankfurters for 2 minutes, then the peppers until all mix well for 2 minute.
- Move the ingredients to the side and add the sauce directly to the pan, let it sit for 5 seconds to cook off the moisture, then mix it with other ingredients.
- Add the pasta, then toss everything together until evenly coated.
