Place a fish fillet on half of the parchment paper.
Place the ingredients for each fillet, that is, a slice of onion, three strips of sweet pepper or paprika, a sprig of marjoram, a slice of lemon, a sprig of parsley, an ounce of white wine, a clean shrimp without the covering, salt and pepper to taste.
Cover the fish with the other half of the parchment paper, rolling the edges to seal.
Place in the oven on a tray at 325 degrees for 30 minutes.