The DU Lounge

1) Those of us who have burnt the roux and had to start all over again

and

2) Those of us who will eventually burn the roux.

Your best bet is to not try to cook it so that it turns brown/black; leave that to the Gulf Coast folks who are real pros at this.
Better to cook it until the roux is the color of dark peanut butter or milk chocolate. Turn off the heat then throw in your "Holy Trinity" (chopped onions, chopped peppers, chopped celery)