Using a food mill, but this time fitted with a fine disk, pass the tomatoes and their juices through and into a bowl.
Heat a large “nonreactive” saucepot over medium heat, add oil, and when hot, add the onion. Cook, frequently stirring, until the onion is “wilted,” about 3 minutes.
Add the carrot and celery and continue cooking for about 10 minutes until the onion is golden brown.
Add the tomato pulp, the juices, and the bay leaves and bring to a boil. As soon as the sauce reaches a boil, lower the heat to a “lively simmer” and cook until the sauce thickens to desired thickness or about 45 minutes. Be sure to continue stirring throughout the entire process.
Before serving with pasta, remove the bay leaves, taste, and adjust seasoning with salt and pepperoncino pepper.