Split pike lengthwise. Sprinkle heavily with garlic salt, salt and pepper. Place in shallow pan on aluminum foil and brush lightly with vegetable oil. Place skin side down. Bake at 450 F 15 minutes.
Slice a burmuda onion thinly and place on fish. Pour cream sauce over the onion covered paked fish.
Mix butter with flour to make a paste. Slowly add cream to make a smooth, medium consistency. Heat saucepan untill no "flour" taste is left in sauce. Pour over fish.