Method

• 1.
  To make tomato seeds and skin mixture, preheat oven to 180°C. Grease 2 baking trays and line with baking paper.
• 2.
  Spread tomatoes, onion and garlic evenly across prepared trays, then season with 1 tbs salt flakes and 1 tsp freshly ground black pepper. Divide oil evenly between trays and toss to combine. Roast, swapping trays halfway, for 45 minutes or until tomatoes are blistered and onion has softened. Set aside to cool for 30 minutes, then stir through basil.

• 3.
  Pass tomato mixture through a mouli or nylon sieve into a bowl. Repeat several times, together with the seeds and skins, to extract as much juice as possible. Reserve tomato juice for use in passata or pasta sauces and collect any remaining seeds and skins to make the tomato conserva.
• 4.
  For the conserva bruschetta, preheat oven to 100°C. Grease a large baking tray and line with baking paper.
• 5.
  Spread tomato seeds and skin mixture over prepared tray and roast for 1 hour 45 minutes or until slightly charred around the edges.
• 6.
  Transfer roasted seeds and skin to a bowl and, using a stick blender, whiz until smooth, then tightly pack into a sterilised jar. Cover with a 1cm-deep layer of oil and store, chilled, for up to 1 month.
• 7.
  To make bruschetta, spread tomato conserva onto grilled sourdough and drizzle with extra oil. Scatter with chilli flakes, oregano and thyme to serve.