very simply take a fillet of any fish you like, bake in the oven drizzled with a bit of olive oil and white wine, add salt and pepper. I also add shredded ginger, chilli, maybe a pinch of hot paprika depending on what fish I use, adn maybe also roast a few tomatoes with it. The trick here is timing, as you dont want to overcook it. Serve with your choice of carb and fresh stir fried or steamed veggies.
My other favourite is fresh or frozen whole sardines, gut and head them, pop under a hot grill or on a barbiw, just a bit of salt and pepper, and I serve them on my homemade wholemeal seed bread.
Take a whole mackarel, stuff the cavity with sliced lemons, samphire, shredded cabbage or other veggies, wrap in foil and bake.
I also make a mean Thai fish curry, start making it as usual with veggies, thai curry paste (I prefer yellow for this) and coconut milk, and at the end add in chunks of fish. You need a good firm fish like ling (not sure if you get that your side of the pond) and make sure you dont stir after you add it, you're basically poaching it in the sauce. Serve with jasmine rice or rice noodles.
I'm hungry now.