
Spaghetti Napolitan
Japan’s beloved café spaghetti, tossed in a sweet, buttery ketchup sauce with onions, peppers and mushrooms, pure, sweet, nostalgic comfort.
- 25 min total
- 15 min hands-on
- Anyone can make this
- Serves 2
- About $1.98 a serving
- 640 calories
- Vegetarian

Dolly says: I’d make this on a weeknight. It’s on the table in 25 minutes.
Ingredients
For 2 servings.
- 8 oz spaghetti
- ½ yellow onion, thinly sliced
- 1 green bell pepper, thinly sliced
- 4 oz white mushrooms, sliced
- 2 tbsp butter
- ⅓ cup ketchup
- 2 tbsp grated parmesan
From your pantry
- 1 tbsp salt
- 1 tsp soy sauce
- ¼ tsp black pepper
Each serving has about 640 calories, 20 g protein, 108 g carbs and 15 g fat, and costs about $1.98 at typical US grocery prices. Both are estimates from what the recipe uses.
Missing something?
- No spaghetti? Fettuccine works.
- No yellow onions? White onions or red onions work.
- No green bell peppers? Red bell peppers or yellow bell peppers work.
- No butter? Ghee works.
- No grated parmesan? Parmesan wedge works.
Steps
Tap an underlined word for a quick explanation.
Fill a large pot with water, add the salt, cover and over high heat.
Bring to a boil. It means heating a liquid on high until it’s fully boiling before you move on. A lid on the pot gets it there faster, which makes it a good moment to chop something.
How you’ll know: Big bubbles break all over the surface, and they keep coming when you lift the lid.
High heat
Cook the spaghetti for the full time the package says.
High heatTimer: 10 min
Dolly’s tip: This one is meant to be soft, not al dente. That’s how it’s made in Japan.Meanwhile, the onion and pepper and slice the mushrooms.
Thinly slice. Thinly slicing means cutting slices about an eighth of an inch thick, roughly two coins stacked. Thin slices cook in seconds and soften fast, which quick dishes need.
How you’ll know: A slice bends a little when you hold it by one edge, and slow, steady cuts beat fast ones.
the butter in a large over medium heat. Add the onion, pepper and mushrooms and cook 4 to 5 minutes, stirring, until soft.
Melt. Melting means gently heating something solid, like butter or cheese, until it turns liquid. Low or medium heat keeps it from browning or burning.
How you’ll know: It’s smooth and liquid, and butter may foam a little but hasn’t turned brown.
Skillet. A skillet is a frying pan: wide and flat with low, sloped sides. The shape lets steam escape, so food browns instead of stewing.
How you’ll know: It’s the pan you’d fry an egg in, and a 10 or 12 inch one handles most recipes.
Medium heatTimer: 4 min 30 sec
Stir in the ketchup and soy sauce and cook 1 to 2 minutes, until the ketchup darkens a shade.
Medium heatTimer: 1 min 30 sec
Dolly’s tip: Cooking the ketchup takes away its raw tang and makes it taste sweet and rich.Scoop out ½ cup of and the spaghetti. Add it to the with a splash of the water and until every strand is orange and glossy.
Reserve pasta water. It means scooping out a cup of the starchy cooking water before you drain the pasta. A splash helps the sauce cling and turn silky, and it’s the step everyone forgets.
How you’ll know: A mug of cloudy water is sitting by the stove before the pasta goes into the colander.
Drain. Draining means pouring off liquid, like tipping pasta into a colander or spooning extra fat out of the pan. Pour hot grease into a can or jar, not the sink, where it hardens and clogs the pipes.
How you’ll know: Only a few drips are left, and the food isn’t sitting in a puddle.
Skillet. A skillet is a frying pan: wide and flat with low, sloped sides. The shape lets steam escape, so food browns instead of stewing.
How you’ll know: It’s the pan you’d fry an egg in, and a 10 or 12 inch one handles most recipes.
Toss. Tossing means gently lifting and turning food so everything gets coated, like pasta in sauce or vegetables in oil. It coats every piece evenly without mashing anything.
How you’ll know: Every piece looks glossy or evenly coated, with no dry spots hiding underneath.
Medium heat
Serve with parmesan and black pepper on top.

Plan this in Dollop, and get the grocery list
Dollop puts this dinner on a night that suits your week, lists only what you still need to buy, and walks you through each step while you cook.
More dinners like this

Vietnamese garlic noodles
25 min

Air fryer mac and cheese for two
25 min

Air fryer pasta bake for two
25 min

Air fryer tortellini with broccoli
20 min
30-minute dinners ›Vegetarian dinners ›What to make with pasta and parmesan ›What to make with bell peppers and parmesan ›What to make with pasta and bell peppers ›