1. Preheat oven to 1°C (170°C fan forced). Arrange tomatoes on a foil - lined baking tray, cut side up. Drizzle with 1 tbsp oil and season with salt and pepper.

2. On a separate foil-lined tray, repeat with the whole capsicum, onion and garlic.

3. Place both trays in oven and roast the tomatoes for about 1 hour, or until soft and lightly browned. Roast the capsicum, onion and garlic for 30 minutes until lightly charred and very tender. Transfer the capsicum to a bowl and cover with plastic wrap to steam off skin. Peel and discard skin, stem and seeds.

4. Squeeze the flesh from the garlic into a food processor, discarding the skin and add the onion and capsicum. Pulse until chunky. Add the tomatoes and process until combined but still chunky. Season with salt and pepper.

5. Bring a large saucepan of salted water to the boil and cook penne according to packet instructions. Drain penne in a colander. Return the pan to medium heat with the remaining tablespoon of olive oil. Once oil is hot, add chorizo and cook until lightly browned, adding the chilli flakes after 2 minutes.

6. Add the tomato sauce to the pan and stir to combine. Add the pasta and toss to coat. Fold in basil and divide evenly among 4 shallow serving bowls. Garnish with shaved parmesan and serve.

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