Set the oven to 220C/200C fan/gas mark 7.

Bring a large pan of salted water to the boil. Halve the potatoes lengthways and trim the fennel bulb, reserving the fronds for later. Cut the fennel bulb into eight wedges and add them to the salted water with the potatoes and cook for 6-7 minutes.

Drain the vegetables in a colander and leave to steam-dry for a minute. Place them in a large roasting tray and season well with salt and pepper. Sprinkle over half the parsley and all the garlic, dot the butter around the tray and drizzle well with olive oil. Combine the ingredients in the tray then level them out into an even layer. Cook in the oven for about 30 minutes, or until golden.

Prepare the salmon while the vegetables are cooking. Pinch the fillets or steaks so they plump up and use the length of a knife to score the skin side about 1cm deep. Season both sides of the salmon and stuff the remaining parsley and mint leaves into the scores.

Once the potatoes are cooked take them out of the oven and sprinkle the grated parmesan over them. Shake the tray lightly, then lay the salmon on top, skin side up. Sprinkle the lemon zest over the top, drizzle with olive oil then cook for 15 minutes.

Just before removing the salmon from the oven, chop the reserved fennel fronds. Sprinkle them over the finished dish then serve it with some wedges of lemon.