Prepare the vegetables by washing tomatoes, peeling and chopping onions, and dicing green and hot peppers.

Combine tomatoes, onions, peppers, and garlic in a large pot.

Cook the vegetables until softened, then puree them through a sieve or food mill into a very large stock pot.

Add oil, salt, basil, sugar, oregano, and tomato paste to the pureed vegetable mixture.

Stir all ingredients together thoroughly.

Simmer the sauce over medium-low heat for approximately 1 1/2 hours, or until the sauce reaches the desired consistency, stirring occasionally to prevent sticking.

While the sauce is simmering, prepare canning jars and lids according to canning guidelines.

Carefully ladle the hot spaghetti sauce into the prepared jars, leaving the appropriate headspace.

Remove air bubbles and adjust headspace as needed.

Wipe the rims of the jars clean and place the lids on top, securing with canning rings.

Process the filled jars in a hot water bath canner according to USDA guidelines.

Process pint jars for 5 minutes and quart jars for 10 minutes, adjusting processing time for altitude.

After processing, carefully remove the jars from the canner and allow them to cool completely on a towel-lined surface.

Check the seals of the jars after cooling.

Store properly sealed jars in a cool, dark place.

Cooked ground beef can be added when jars are opened for serving.