Add all the ingredients to a large stock pot and bring to a boil. Immediately turn your heat down to low, cover the pot, and allow it to simmer on low for one hour.
After one hour, check on the sauce and stir well. Crush the tomatoes in the process. Re-cover your stock pot and allow it to simmer on low for another hour.
Remove the pot lid and stir sauce. Allow to simmer one hour or longer until the sauce thickens.
Once the sauce has thickened sufficiently, remove the pot from heat and allow the sauce to cool for 10 minutes.
Place food mill over a deep bowl or pot and carefully transfer some of the sauce to the food mill. A soup ladle works well for this process.
Crank the food mill as the finished sauce drops into the bowl below. The skins and other debris will remain in the food mill.
Once all the sauce has been processed through the food mill, discard the skins and other debris. Decant the sauce into a jar, place the lid on the jar, and refrigerate.