Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2). Wash potatoes thoroughly and drain well. Spread sea salt evenly on a baking tray. Place potatoes on top and bake in the oven on the middle shelf for about 40 minutes.
Rinse trout cold and dab dry. Season inside and outside with salt and pepper. Turn fish in flour. Melt half of the butter in a large pan, fry 2 fish briefly on each side, remove.
Melt the rest of the butter and fry the other fish in it as well. Wrap each fish in a piece of parchment paper in such a way that they lie in an open parcel.
Put the fish parcels on a fat pan (deep baking tray). Slide potatoes on the tray onto the lowest rail. Fry fish on the middle shelf for 15-20 minutes at the same temperature.
Rinse chives cold, shake dry and cut into small rolls. Season crème fraîche with salt and pepper, whip briefly with a hand blender, stir in chives.
Cut the potatoes slightly and press them apart slightly. Fill in the cream of chopped garlic. Serve the salmon trout with baked potatoes.