Scatter the bread crumbs on a rimmed baking sheet and bake about 5 minutes or until dry and golden; dump crumbs into a mixing bowl.
In the container of a food processor; add the crawfish (fat too, if any) and tasso; pulse just enough times to mince the mixture (stop short of pureeing); add crawfish mixture to the mixing bowl with the breadcrumbs.
Melt the butter in a medium skillet over medium heat.
Stir in the onions, celery, and bell pepper; saute/stir briefly until the vegetables are soft.
Stir in the lemon juice, Worcestershire sauce, Tabasco, salt, and cayenne and remove from the heat.
Scrape the mixture into the mixing bowl; also add in the egg and combine mixture.
Form mixture into 8-12 patties, no thicker that 1/2 inch.
The mixture will be a little fragile.
Coat the patties with the cracker crumbs by holding each patty in your hand and sprinkling both sides with cracker crumbs.
Refrigerate patties for about 10 minutes.
Warm 1/4 inch of oil in a large skillet over medium heat; fry the patties 2-3 minutes on each side or until golden brown.