Boil the potatoes in enough water for about 25 minutes. Remove, cut in half and place on a baking tray. Add capers, diced garlic, olive oil and sliced olives and season with rosemary and sea salt.
Bake in the preheated oven for about 25 minutes.
Sea bream with ours Fish seasoning rub in. Remove the baking tray from the oven and turn the potatoes over. Push to the side and place sea bream on top.
Bake vegetables and fish in the oven for another 35 minutes.
Remove the tray and serve the sea bream with rosemary potatoes.
