Transfer the prepped tomatoes to a large stock or soup pot.
Add the chopped onions, grated garlic, chopped bell peppers and chilies, if using.
Over medium heat, cook the vegetable mixture for 30 minutes; stirring often.
Next, ladle the cooked vegetables into a blender and, working in batches, puree until smooth; be careful to not overfill the blender as these ingredients may be very hot; alternatively, use a handheld immersion blender to puree everything, in one batch, right in the pot.
Next, add all of the remaining ingredients and stir well; continue to cook, stirring often, for another 90 minutes.
While the sauce is cooking, prepare the jars and canner.
Once the sauce is cooked, use a canning funnel and a ladle to spoon the sauce into the Mason jars, leaving ¾-inch of headspace in each jar.
Use a non-metallic bubble remover to remove any air bubbles.
Wipe down the rim of each jar, with a damp paper towel, to ensure none of the sauce has come in contact with the rim.
Apply the lid until fingertip tight.
Fill the water bath pot with sufficient water to cover the jars and bring to a boil.
Using a jar lifter, place the jars into the water bath canner with the boiling water.
Place a lid on the pot and boil the jars for 20 minutes.
Once done, carefully remove the jars using the jar lifter and place them onto a wire cooling rack that has been covered with a clean kitchen towel.
Leave the jars to cool for a minimum of 12 hours.
Once cooled, wipe the jars of any residue that might have been transferred to the outside of the jar during the boiling process.
Label the jars and store them in a dark, cool cabinet.
