Preheat your oven to 180°C (fan 160°C/gas mark 4). Heat half of the olive oil in a large, hob-proof casserole dish or ovenproof saucepan over a medium to high heat. Slide in the onion, leek and sliced bacon and fry, stirring occasionally for 4 minutes, or until the onions and leek are starting to soften.
Add the chopped garlic and mushrooms and continue to stir-fry for 2 minutes. Squeeze in the tomato puree and stir through the mixture. Add the paprika and the rice and continue stir-frying for 30 seconds.
Pour in the stock and bring to the boil, before clamping on a tight lid and transferring to the preheated oven. Bake the rice for 12 minutes.
While the rice is cooking, heat up half the remaining oil in a large frying pan over a high heat. Season the cod with salt and pepper and when the oil is hot, carefully lay three fillets in. Brown on both sides – you are not trying to cook the fish through here, just to brown it. Remove the browned cod to a plate and repeat the process with the remaining oil and fish.
After 12 minutes, take the risotto from the oven, remove the lid and give the rice a good stir. Lay the fish and tomatoes on top of the rice and then slide the dish back into the oven, uncovered. Roast the whole lot for 10 minutes, until the fish is perfectly cooked through and the tomatoes are softening but still holding their shape.
Remove the risotto from the oven, sprinkle with parsley and serve up with the lemon wedges.