All-Purpose Roasted Tomato Sauce

Preheat the oven to 180°C (350°F/Gas mark 4).

Place the tomato halves, cut-side up, on two baking trays, along with the onion wedges and garlic cloves. Drizzle the olive oil over the top and season with the salt and pepper, then mix well with your hands.

Roast for up to 45 minutes, or until the tomatoes are blistered and the onion is starting to soften and brown. Remove the trays from the oven and set aside to cool for 15 minutes.

Tip everything into a bowl and, once cool enough to handle, squeeze the garlic out of their skins and mix through the tomato and onion, breaking everything up with a fork. Add the basil leaves if you want some extra flavour.

You can serve the sauce as is, tossed through hot pasta, or blitz in a food processor for a smooth consistency, or run the mixture through a mouli. If you want your passata to be thicker, slowly simmer it in a saucepan over low heat until it reaches your desired consistency.

For pizza sauce, reduce the sauce even further until thick and rich.

The sauce will last for 4-5 days in the fridge or up 3 months in the freezer.

To preserve your passata, follow the instructions to sterilise jars or bottles. Then using a funnel, fill the hot jars up to the thread with the hot passata (reheat it if necessary). Wipe the rim with a clean cloth and seal. Heat-process the jars, following the instructions below, for 1 hour and then store in a cool, dark place for up to 1 year.

You'll need 3-4 x 500ml jars or bottle with metal lids. To sterilise jars or bottles, give them a wash in hot soapy water and a good rinse or run them through the dishwasher, then place them upright in a baking dish in a cold oven. Heat the oven to 110°C (225°F) and, once it has reached temperature, leave the jars in the oven for about 10–15 mins, or until completely dry, then remove them carefully. Lids should boiled in water for 5 minutes, or run through the dishwasher and then left to air-dry.

Get the biggest pan you have, such as a stockpot, and put it on the stovetop. Lay a folded tea towel in the bottom of the pan, then sit your filled, lidded jars on the tea towel. Make sure your lids aren’t on too tight! Pour in enough warm water to cover the jars, either completely or at least until three-quarters submerged. Bring to the boil over medium heat and simmer for 1 hour. Carefully remove the hot jars from the water using preserving clamps or a very thick cloth. Line your jars up on the benchtop and let them sit overnight. As they cool, a vacuum will form inside each jar and suck down the lid, sealing them securely. These jars can be safely stored in the pantry for up to 1 year. Once opened the passata will need to be used with 3-4 days.