We, living here in the western U.S., enjoy trout regularly. My opinion is that it should be prepared as though just caught at creek (pronounced 'crick' here) side. Dredge the trout (cut off the heads if you like) in about 1/2 cup of flour with a couple of pinches of grey salt and as much fresh ground pepper as you'd like. I place the flour, etc., in a plastic storage bag into which goes the fish... shake enough to evenly coat the trout. In a skillet (has to be cast iron for me) heated to medium heat, with just a little oil, maybe enough to cover the bottom slightly, place the fish. Cook about 3 minutes per side. It should be browned somewhat, but don't overcook. That's it! Your jacket potato (is that boiled or baked?) sounds good, but fried would be a better accompaniment to this style of fish. Actually, we like to boil the potatos, slice thickly with one medium sweet onion and fry it until potatos begin to brown.
Enjoy!