Use 1 sack crawfish (about 40 lbs.) Scald crawfish in almost boiling water for about 15 min. Drain and cool. Peel crawfish and save the fat in a separate bowl. Clean abt. 200 heads to stuff. To make gravy: Grind onions, celery bell pepper, garlic and parsley. Make roux with oil and flour. Stir constantly until browned. Add ground seasonings. Cook on low fire abt. 30 min. Add tomato paste and crawfish fat. Cook abt. 30 min more. Add hot water and let cook on low fire. Add ground crawfish tails, add salt and pepper. Cook on high fire abt. 20 min. Add baked crawfish heads. Cook on low fire abt. 1 hr. More hot water may be added if too thick. Stir carefully. Serve in soup bowls over rice. To make stuffing for heads: Grind onions, celery, bell pepper, garlic and parsley. Fry crawfish and ground seasonings in hot cooking oil; cool. Add cawfish fat and eggs. Mix in bread crumbs, salt and pepper. Stuff heads. Dip the stuffed part of head in flour and place on cookie sheet. Bake for 20 min in 200ºC . oven.