Slice sausage; cook in 1 tablespoon hot oil in a Dutch oven over medium-high
heat for 5 minutes.
Remove sausage; drain. Reserve drippings in skillet. Add 1 tablespoon oil; reduce
heat to medium. Cook mushrooms 5 minutes or until brown. Add to sausage.
Remove skillet from heat; add brandy. Return skillet to heat; cook for 1 minute.
Stir in flour and remaining 4 tablespoons oil; cook, stirring to loosen browned
bits, for 8 minutes or until roux is the color of chocolate.
Stir in Cajun seasoning, next 5 ingredients, and white parts of green onions;
cook, stirring constantly, 7 minutes.
Add broth; cook, stirring constantly, for 5 minutes.
Return sausage and mushrooms to pan; cook for 20 minutes.
Add hot sauce to taste. Discard bay leaves. Sprinkle with filé powder, if desired.
Top with green parts of green onions.