Cut haddock fillets into serving size pieces.
Dice 2 strips of bacon; cook until crisp. Remove bacon; cook onion in remaining bacon drippings until soft. Combine cooked bacon with onion, bacon drippings, parsley and bread crumbs. Season with salt and pepper.
Spread bread crumb mixture on half of the haddock pieces.
Top with remaining haddock pieces.
Arrange haddock in a greased shallow baking dish.
Halve remaining two or 3 bacon strips and place on fish.
Bake at 325° F. for 40 to 45 minutes.