From BBC GoodFood
1 large fennel bulb
6 medium sized potatoes, peeled and thinly sliced
8 tablespoons olive oil
8 cloves garlic
8 sprigs fresh rosemary
2-3 whole fish, such as bream, bass or trout, total weight about 1.5kg, gutted and scaled
2 x 275g packs cherry tomatoes on the vine
Heat the oven to 190C, Gas 5.
Roughly chop the fennel and blanch for 1 minute. Put all the potato slices and fennel in a large shallow roasting tin and pour 6 tablespoons of the oil over them. Bash 4 of the garlic cloves, skins still on, with the flat side of a knife. Season the potatoes generously and tuck in the garlic cloves and 4 sprigs of the rosemary, broken up a bit. Toss the potatoes with the other ingredients to coat them in olive oil, then arrange in the tin and cook in the oven for 15 minutes.
Wash and dry the fish inside and out. Peel and slice the rest of the garlic. Make 3 slash marks across each fish on both sides with a sharp knife and push in some garlic slices and rosemary sprigs.
Season inside and out. Drizzle about a tablespoon of oil over the fish and rub it on. Take the potatoes out after 15 minutes and lay the fish on top of them with the sprigs of tomatoes.
Give a final drizzle of oil, then roast until the potatoes and the fish are cooked through, about 25-35 minutes.
Serve on a large flat dish with a green salad.