Trim, quarter, and place tomatoes into a large stockpot
Bring to a boil, stirring occasionally
When tomatoes have softened, either blend with a hand blender, or run through a food mill. If using a food mill, the skins and seeds can be discarded. Reserve 1 cup of tomato juice (for thickening later). Simmer down to about a third or hals of the original liquid volume. (2 to 3 hours)
Add the vinegar, tomato paste, sugar, and spices. Bring to a simmer.
Place 1/3 cup clear gel (heaping) into a bowl. Slowly whisk in the reserved tomato juice and whisk into the simmering tomato ketchup.
Pour ketchup into jars and place lids and bands onto each jar. Tighten the band to finger-tight.
Place jars into water bath canner. Cover with 1 to 2 inches of water. Boil for 10 minutes, covered, from the time the water boils.
Transfer jars to a heat resistant surface. Allow jars to sit for 24 hours, then verify they have sealed.