Tomato passata

Heat the oven to 170C/150C fan/gas 3. Quarter the tomatoes and use a sharp knife to remove and discard the seeds. Tip the tomato flesh onto a large baking tray along with the garlic. If the tomatoes came on vines, put these into the roasting tin, too, to increase the tomato flavour. Drizzle with the oil and season lightly. Cook in the oven for 1 hr until the tomatoes have roasted and the garlic cloves are soft. Slow-roasting the tomatoes will not only concentrate the flavour, but fill your house with the most wonderful aroma.

Tip the tomatoes into a food processor, squeeze in the garlic, removing the skins, and add any scrapings from the tray. Add a handful of basil leaves, if you like. Put a fine sieve over a large bowl. Blend the tomatoes until smooth, then push them through the sieve into the bowl.

Sterilise the jars by washing them in hot, soapy water, rinsing and putting them in an oven heated to 160C/140C fan/gas 3 for 10 mins. Leave to cool. For ease of pouring, put the passata into a large jug, then fill the sterilised jars to the tops. Seal with the lids. The passata will keep in a cool, dark place for three months. Keep in the fridge once opened and consume within a month.