Preheat your oven to 180°C. To make the stock, line a tray with baking paper and add the red mullet bones. Drizzle over a little olive oil and season with salt and pepper. Roast for 10–12 minutes, until golden brown.
Put the 20ml of the olive oil into a high-sided pan on a medium heat. Add the garlic and onion, season, and allow to caramelize for around 12 minutes. Add the choriceros, chilli and smoked paprika, and cook until it resembles a strong paste. Add the prawn stock and the roasted bones and cook on a very low heat, for 15–20 minutes. Place a sieve over a bowl, and strain so you are left with a smooth stock. You will need 800ml for this recipe.
To cook the rice, put 50ml of olive oil into a casserole pan on a medium heat. When hot, add the julienned onion and bay leaf and cook very slowly until golden brown (around 8–10 minutes). Add the tomatoes, using a fork to squeeze the juice out. Cook for 10 minutes, to bring everything together. Add the rice and cook for a couple of minutes to release the starch. Only then start to add the stock: just enough to cover the rice at first, then little by little, stirring continuously (almost as though you’re making risotto) until the rice is al dente. Rip the basil – I always rip it, as cutting turns it black – and stir through the rice. Turn off the heat.
In the meantime, put the remaining 30ml of olive oil into another pan on a medium heat. When hot, add the red mullet, skin side down. Cook for 1½ minutes on the skin side to get it crisp, then season, turn and cook for 20–30 seconds on the other side. Serve the rice on plates with the mullet on top of the rice, skin side up. Drizzle with a little more olive oil, sprinkle with salt, and serve.