Jamie Oliver's Homemade Ketchup

Ingredients:

• 450g cherry or plum tomatoes, halved; additional 450g canned plum tomatoes, chopped
• 1 large red onion, peeled and coarsely chopped
• 1/2 fennel bulb, trimmed of greens and roots, coarsely chopped
• 1 stalk celery, leaves removed, coarsely chopped
• Olive oil
• Thumb-sized piece of ginger, peeled and coarsely chopped
• 2 cloves garlic, peeled and sliced
• 1/2 fresh chili pepper, seeded and finely chopped
• A bunch of basil, separate the leaves, chop the stems
• 1 tbsp. coriander seeds
• 2 umbrellas of carnations
• Sea salt
• 1 teaspoon ground black pepper
• 3/4 cup and 2 tablespoons red wine vinegar
• 1/3 cup fine brown sugar

Preparation:

1. Place the onion, fennel, and celery in a large, heavy-bottomed saucepan with plenty of olive oil. Add the ginger, garlic, chili, basil stems, coriander seeds, and cloves. Season with pepper and a good pinch of salt. Cook over low heat for 10–15 minutes, stirring occasionally, until softened.
2. Add all the tomatoes and 1.5 cups of cold water. Bring to a boil and simmer until the sauce is reduced by half.
3. Add the basil leaves, then puree the mixture in a food processor or with a hand blender and press through a sieve twice to make it smooth and shiny.
   
   Place the sauce in a clean saucepan and add the vinegar and sugar. Place the mixture over low heat and simmer until the sauce thickens to the consistency of ketchup. Adjust the seasonings to taste at this point.
4. Pour the ketchup through a boiled funnel into sterilized glass bottles, then seal tightly and store in a cool, dark place or in the refrigerator until ready to use. Store for up to 6 months.