1: Preheat the oven to 220°C/Fan 200°C/Gas 7. Check the hake fillets for any pin-bones.

2: Put the potatoes into a large pan and add enough water to cover by 5cm. Bring to the boil, lower the heat and simmer for 5 minutes. Drain the potatoes and lay them in the bottom of an ovenproof dish (about 28cm in diameter and 7.5cm deep).

3: Scatter the onion and fennel slices in an even layer over the potatoes. Pour on the stock and sprinkle on the saffron and a little salt and pepper. Cover with foil and bake in the oven for 15 minutes.

4: Take the dish out of the oven and add the cherry tomatoes. Re-cover with foil and return to the oven for 8 minutes.

5: Take the dish from the oven and remove the foil. Season the fish fillets on both sides with salt and pepper and lay them on top of the vegetables. Add the olives and baste the fish with the saffron stock. Return to the oven, uncovered, and bake for 8 minutes.

6: Sprinkle with chopped parsley, zest over the lemon and drizzle with the extra-virgin olive oil. Serve with aïoli on the side, and provide crusty bread to mop up the delicious juices if you like.