a Roux is a living breathing thing -
You can start your Roux to make your Gumbo and then give some of the Roux to your friends and they can expand/keep the Roux (going)
"More than anything else, it's the roux that gives gumbo its particular character. Making roux is something of an art. It may take some practice to get good results."
One way to make a Roux