Yes it is a dish of three parts.
Make the sauce (garden tomatoes from last year) a bit of spicy chorizo, minced...saute that in olive oil, then onions and garlic and red pepper flakes, then the tomato sauce and good briny green olives and allow to simmer until fairly thick.
Separately prepare potatoes. At this time of the year I can get potatoes from the Ile de Re which are great; small, very thin papery skins which you do not remove. Boil the potatoes in well salted water until not quite cooked, drain and allow them to dry a bit and then while still hot toss them with olive oil and roast in a very hot oven until they begin to brown but are not quite deeply browned. Remove.
Season a thick piece of fish (I like the back of cod) with white pepper, salt and smoked paprika. I then add a few drops of olive oil to the fish and massage it well before allowing it to sit for 15 minutes or so. Heat olive oil in a heavy saute pan over moderately high heat until it begins to smoke. Add the fish - presentation side down - and sear without disturbing for about three minutes. Turn the fish (the presentation side should be deeply colored) and immediately turn the heat off. Allow to sit in the cooling pan off the burner as you assemble for final cooking and presentation. The fish is essentially seared and browned at this stage but very nearly raw.
Pool all but about 1/4 cup of the sauce in the center of an appropriate baking dish. Place the fish atop the pooled sauce. Toss the reserved sauce with the roasted potatoes in a large bowl and arrange them along the edges of the baking dish. The dish can be held at this point for a few hours...making it a great fish dish for dinner parties where you want less fuss.
To finish roasting, tent the fish loosely with a piece of foil and place the baking dish in a preheated hot oven - say 450 - for about 12 - 15 minutes depending on thickness of fish.
Fast and easy, and tasty.
