Pour the tomatoes into a large bowl and crush them using your hands. Reserve.

In a large skillet, heat the olive oil and sauté the garlic and the onion. (I like to add the garlic with the oil and let them heat together so the garlic can infuse the oil).

Add the tomatoes and the basil and let it boil.

Once it boils, lower the heat and let it simmer for 1.5 to 2 hours, stirring every now and then.

Remove the basil and season with salt (and sugar, if necessary).

Optional: Blend the sauce until smooth using a hand blender.

Let it cool before adding to the pizza dough.