Line your pan with aluminum foil. Spray with Pam Olive Oil Spray. Rub butter over both sides of filets and shake the natures seasonings, salt and pepper on both sides. Sometimes I may add a couple dashes of another season, it just depends.
Lay a few slices of onion (to desired taste) on each filet. Cover with foil, put in over and bake for 45-50 min. at 350 degrees