Wipe fish with damp cloth; set aside. Shake flour into empty brown-in-bag. Sprinkle fish inside and out with salt and pepper.
Combine 1/4 cup butter, stuffing, onion, parsley and carrots: stuff cavity and secure opening with toothpicks or bind with soft string. Place stuffed fish in bag; brush with remaining butter and sprinkle outside with paprika. Close bag loosely with twist tie about 2-inches from fish. (Bag should fit loosely over food.) Puncture six 1 slits in top of bag with paring knife. (These allow air and water vapors to escape from bag.)
Cook in 350° F oven about 1 hour. Remove pan from oven; allow to sit and cool several minutes. To remove fish, slit open top of bag with paring knife or scissors. (Steam escapes when bag is split, so use care not to burn yourself.) Remove fish to serving platter.Servings: