Wash tomatoes. Dip in boiling water 30–60 seconds or until skins split, then dip in cold water. Slip off skins, remove cores, and quarter.
Combine tomatoes, onions, and cayenne peppers; boil gently until vegetables are soft.
Press the mixture through a food mill or sieve and return the pulp to the saucepan.
Add vinegar, sugar, salt, paprika, allspice, cinnamon, and cloves. Boil gently while stirring frequently until the mixture is reduced to the desired ketchup consistency.
Fill hot pint jars, leaving 1/8-inch headspace.
Process pints 15 minutes at 0–1,000 ft, 20 minutes at 1,001–6,000 ft, or 25 minutes above 6,000 ft.