|Preparation||Cooking||Start to finish|
|24 min.||32 min.||56 min.|
|1||Poach 800 g fish in 1 litre fish fumet (or, at a push, just use salted water with 1 Bouquet garni) at a gentle simmer until just cooked.|
To ensure the fish is perfectly cooked, stick an electronic thermometer into the fish and cook until the temperature reaches 140°F (60°C).
|2||Take the fish out of the cooking liquid, remove the skin and any bones, then flake (break up) the flesh.|
|3||Prepare and slice 2 onions finely (a mandolin is the ideal tool for this).|
|4||Pour 3 tablespoons olive oil into a saucepan on medium heat. When hot, add the sliced onions.|
|5||Salt and pepper, then cook for about 5 minutes - the onions don't need to brown.|
Preheat the oven to 360°F (180°C).
|6||Peel 800 g cooked potatoes (I'm using rattes here).|
|7||Cut the potatoes into small pieces, then mash coarsly with a fork.|
|8||Add the fish, onions, thyme, salt and pepper, and mix well.|
|9||Fill individual ramekins or a large gratin dish.|
Top with grated cheese.
|10||Bake for 20 minutes, just until the cheese on the top has melted and is nicely browned. Finish browning under the grill if necessary.|