
Spaghetti with tomato butter sauce
A can of tomatoes, a stick of butter and a halved onion simmer into the sweetest, silkiest tomato sauce you have ever made, with almost no chopping.
- 60 min total
- 15 min hands-on
- Anyone can make this
- Serves 4
- About $1.22 a serving
- 630 calories
- Good the next day
- Vegetarian

Dolly says: Make the full amount. It’s just as good for lunch the next day.
Ingredients
For 4 servings.
- 1 yellow onion, peeled and halved
- 1 can crushed tomatoes, 28 oz
- ⅓ cup butter
- 1 lb spaghetti
- ½ cup grated parmesan, to serve (optional)
From your pantry
- 1½ tbsp salt, divided
Each serving has about 630 calories, 19 g protein, 103 g carbs and 17 g fat, and costs about $1.22 at typical US grocery prices. Both are estimates from what the recipe uses.
Missing something?
- No yellow onions? White onions or red onions work.
- No crushed tomatoes? Diced tomatoes work.
- No butter? Ghee works.
- No spaghetti? Fettuccine works.
- No grated parmesan? Parmesan wedge works.
Steps
Tap an underlined word for a quick explanation.
the onion and cut it in half through the root.
Peel. Peeling means removing the skin with a vegetable peeler or a small knife. It takes off tough or bitter skins, though potato and carrot skins are fine to leave on unless the recipe insists.
How you’ll know: The color underneath is even all over, with no patches of skin left behind.
Dolly’s tip: No chopping needed. The onion flavors the sauce and comes out at the end.Put the crushed tomatoes, butter, onion halves and ½ teaspoon salt in a medium and over medium heat.
Saucepan. A saucepan is a pot with tall, straight sides and one long handle. It’s for things that need depth, like rice, sauces or a few boiled eggs.
How you’ll know: The food fills it about halfway, leaving room to bubble without spilling over.
Simmer. Simmering means keeping a liquid just below a boil, with small bubbles rising gently. It cooks food evenly and lets a sauce thicken without scorching on the bottom.
How you’ll know: Small, lazy bubbles break the surface every second or so, and nothing is churning.
Medium heat
Turn the heat to low and let it bubble gently, uncovered, for 40 minutes, stirring now and then.
Low heatTimer: 40 min
Dolly’s tip: Tiny lazy bubbles are right. If it spits at you, turn it lower.When the sauce has 15 minutes left, fill a large pot with water, add 1 tablespoon salt, 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 1 minute less than the package says, until .
Al dente. Al dente is Italian for “to the tooth”: pasta cooked until tender but with a slight firm bite in the center. It holds up in sauce and keeps softening a little after you drain it.
How you’ll know: Bite a piece a minute before the package time: tender, with a slight firm bite in the middle and no crunch.
High heatTimer: 9 min
Fish out the onion halves with a fork and set them aside. Taste the sauce and add salt if it needs it.
Dolly’s tip: The soft onion is a cook’s treat. Eat it on toast.Scoop out ½ cup of , the spaghetti, and it with the sauce, adding of pasta water if it looks thick.
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.
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.
Splash. A splash is a small, quick pour, about a teaspoon to a tablespoon. It’s there to loosen or brighten a dish, so the exact amount doesn’t matter.
How you’ll know: The dish looks a little looser or tastes a little brighter, not soupy.
Low heat
Serve with parmesan 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.
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