Rue here is mainly a southern thing. It's basically flour, and fat cooked till the flour is browned, and then added to whatever for thickening, and body to the whatever.
Oddly Hot Dogs are one of my favorites. In New York we call them "dirty water dogs" because they steep in warm rancid water to keep warm until they are sold. Best dogs on the planet if you ask me! Ps... I despise Rue.