Homemade Ketchup

Steps

1. 1
   Put the tomatoes, onions and garlic in a wide, heavy pan, cover and cook over medium heat for 30 minutes until completely soft.
2. 2
   Pass through a food mill or rub through a sieve to remove the skins and seeds. A blender leaves the seeds in, and they turn the ketchup bitter.
3. 3
   Tie the cloves, allspice, peppercorns and cinnamon in a muslin bag.
4. 4
   Return the purée to the pan with the spice bag and simmer uncovered over medium-low heat for 90–120 minutes, stirring often, until reduced by about two-thirds. The thicker it gets, the more often you stir, or it will catch.
5. 5
   Add the sugar, vinegar, salt and paprika and cook for 20–30 minutes more. It is ready when a spoonful on a cold plate does not leak a watery ring.
6. 6
   Remove the spice bag, taste and adjust. For a completely smooth texture, blitz with a stick blender.
7. 7
   Ladle the boiling ketchup into sterilised jars, leaving 1 cm of headspace, and seal tightly.
8. 8
   Process the jars in boiling water for 15 minutes and let them cool slowly. Store in a cool, dark place for up to a year; refrigerate once opened.