One taste of homemade ketchup and you will understand why it is worth taking the time to prepare. Please read about pickling and How to Process.
Simmer in a large pot over medium heat, stirring occasionally, until very soft, about 30 minutes:
Puree in a food mill fitted with the medium disk, then return to the pot. Stir in:
Tie in a square of cheesecloth and add to the tomato mixture:
Bring to a rolling boil, then reduce to a simmer. Cook until the sauce is reduced by half, stirring often to prevent scorching. Remove and discard the spice bag. Stir in:
Reduce the heat and simmer, stirring almost constantly, for 10 minutes or until the ketchup is thick enough to be mounded on a spoon. Prepare a water-bath canner, gather all your canning equipment, and have ready 5 clean, hot pint jars. Pack the hot ketchup into the prepared jars, leaving ¼ inch headspace. Remove any trapped air from the jars and adjust the level of the ketchup if needed. Wipe the rims. Place lids on jars and screw on rings until fingertip-tight. Process for 15 minutes. Let cool completely and store as directed.