The famed 3 ingredient tomato sauce is nothing to shrug at. A 40-minute simmer of tomatoes, butter, and onions transforms these meager ingredients into an extraordinary sauce – one you’ll not soon forget.
tomato sauce with onion and butter

When I look for a new recipe, the number of ingredients involved in the recipe isn’t usually something I consider…unless it’s an endless list of ingredients that I don’t have access to.

But a recipe that includes only canned tomatoes, onion, and butter?  Is it a sign from above?  A whisper from the inside of my pantry calling to me?

Quite possibly. And frankly, I’m not going to mess with a whisper from the inside of my pantry.

After 4 days of lugging my shoes around in my carry-on bag thanks to the extra weight needed for the way-more-important swag, cooking a big meal wasn’t at the top of my to-do list when I returned home from BlogHer Food ’11 this week…but a 3 ingredient sauce endorsed by Deb is one that I was willing to take on.

Crack open a can of tomatoes, slice an onion in half, and dice up some butter, then let it all simmer away together for around 40 minutes and watch this unlikely combination (tomatoes and butter – really?) morph into an extraordinary sauce.  The butter smooths out the acidity of the tomatoes and you’re left with a tomato sauce made from canned tomatoes that actually tastes like it was made with vine-fresh summer tomatoes.

After recently finishing up the last of the 13 quarts of fresh tomato sauce I canned and froze last summer, this sauce was such an unexpectedly pleasant surprise to come from pantry ingredients.  The next time this sauce makes it to my menu, I may be tempted to add a couple cloves of garlic, some basil, and a little Parmesan cheese but I doubt that I will.  This tomato sauce stands strong enough on its own and I certainly don’t want to fuss with a good thing.

  • Prep Time: 5min
  • Cook Time: 40-45min
  • Yield: 4 servings


You can, without a doubt, use pureed or crushed tomatoes as I did in this recipe. Reduce the cook time to 35 minutes and don’t worry about crushing the tomatoes against the side of the pot.


28 oz canned whole peeled tomatoes (preferably San Marzano) (see note above)
5 tbsp unsalted butter
1 medium yellow onion, peeled and halved
Salt to taste


  • 01

    Put the tomatoes, onion and butter in a heavy saucepan (it fit just right in a 3-quart) over medium heat. Bring the sauce to a simmer then lower the heat to keep the sauce at a slow, steady simmer for about 40-45 minutes, or until droplets of fat float free of the tomatoes. Stir occasionally, crushing the tomatoes against the side of the pot with a wooden spoon. Remove from heat, discard the onion, add salt to taste.

    Serve with spaghetti, with or without grated Parmesan cheese to pass.

adapted from Essentials of Classic Italian Cooking by Marcela Hazan via Smitten Kitchen