Heat the olive oil and butter in a large saucepan over medium heat. As soon as the butter melts, add the halved onions. You’ll want to cook these for about 5-7 minutes, stirring occasionally until they become transparent and fragrant. The aroma of onions sautéing in butter provides a comforting welcome to your kitchen.

Now, toss in the garlic. Stir it around for about a minute until it’s golden and fragrant. Don’t let it brown too much; we want a subtle, buttery flavor here, not a carbonized crunch.

Now, if you chose fresh tomatoes, you’ll need to peel them. One trick is to blanch them in boiling water for about 30 seconds. Then, quickly transfer them to an ice bath to cool. This makes the skins slide right off. If you’ve gone the canned route, simply pour them into the pan, juices and all.

If using fresh tomatoes, after peeling, chop them up and add them to the pan with the onions and garlic. This is where excitement brews—mix in the granulated sugar and salt. Give it a stir to combine.

Bring the sauce to a gentle simmer. Reduce the heat to low and let it bubble softly for about 30-40 minutes. Stir occasionally, letting the flavors infuse and meld together. If it gets too thick, add a splash of water.

During this time, the house will start to smell like an Italian kitchen, and trust me, you’ll be ready to dig in.

Once your sauce has simmered, add in the balsamic vinegar and chopped fresh basil. Stir it well so all those flavors mingle. Taste for seasoning; a pinch more salt might just elevate it to perfection.

You’re done! Let the sauce cool slightly before using it, or store it in jars to use later.