Score the bottom of each tomato with an X. Place them in boiling water for about a minute until the skins start to wrinkle.
Transfer the tomatoes to an ice water bath to cool. Once cooled, peel off the skins, remove the cores, and set the tomatoes aside in a large bowl.
Blend the tomatoes, onions, garlic, and bell pepper in batches until smooth. Pour the pureed mixture into a large stockpot.
Add butter, olive oil, salt, basil, soy sauce, oregano, brown sugar, pepper, Worcestershire sauce, red pepper flakes, and bay leaves to the pot. Stir well and bring the mixture to a rolling boil.
Once boiling, reduce the heat to low and let the sauce simmer for 2 1/2 hours, stirring every 15 minutes to prevent sticking. This slow simmering will deepen the flavors.
If canning, sterilize jars and lids. Add 2 tbsp lemon juice to each jar, then fill with the simmered sauce.
Seal the jars, place them in boiling water, and boil for 45 minutes. Let the jars cool overnight, then store them in the pantry.