In a heavy 3 qt. saucepan, over medium heat, pre-warm the pan and the olive oil, while you're opening the tomato cans.
Pour the tomato puree into the hot olive oil, and let it "fry" for a minute, stirring occasionally. You'll be surprised how much richness this little extra step adds to your sauce.
Blend in the beef or chicken base now. (This is optional for vegetarian)
Add the onion, garlic, herbs, salt and pepper. The amounts given are approximate; use more or less to your taste. Allow the puree and seasoning to bubble together for a minute. Then stir in the stewed tomatoes* and the wine. (You can leave out the wine, but don't!) Swish the water around in the cans to get all the tomato-goodness, and add the water to the pot.
If you like to add mushrooms and/or other vegetables to your sauce, add them here. We're Italian purists ;) so we don't add anything to our sauce.
Bring sauce to a soft boil, then cover, and reduce the heat to medium low or low. Allow the sauce to simmer a minimum of 30 minutes. (I prefer an hour).
*NOTES: The diced stewed tomatoes are much nicer, but if what I have on hand is the thick-sliced style I prefer to break them up in hand as they go into the pot, so we don't end up with huge chunks of tomato.
This recipe makes a double batch, enough for two casseroles (like my meatball sandwich casserole), or to serve a crowd.
I like to work smart, so I make enough that I can put half in the frig or freezer for a quick-fix meal later.