Cook at medium stirring constantly for about 45 to 60 minutes to achieve a red roux. (about the color of a red brick).
For the Gumbo:
Pan fry sausage in skillet with duck fat. May need to batch in separate skillets until crispy. Dredge and roast duck until done. Debone duck, dice fine and set aside.
To the hot Red Roux add onions, bell peppers, scallions, celery for 4 minutes stirring constantly. Add chicken stock and return to boil. Add prepared duck, sausage, tabasco, cayenne, salt and pepper to taste. Simmer for 1 hour one hour, remove from heat, skim top.
Serve over rice, garnish with green onion tops and parsley. Yield is 1 gallon.