but is it really really necessary to cook it that long?
Someone had me help to make it one night, and insisted that I stand there stirring for a very, very long time.
I don’t know a lot about Cajun cooking, but apparently it takes a long time to develop that dark ‘copper penny’ color and attendant flavor.
https://www.thekitchn.com/tip-how-to-make-a-brown-roux-73211
Chefs and schools in New Orleans lately have been pushing the idea of making roux by adding flour to hot oil.
I have done this many times and it does make a nice roux very quickly. I like a very dark roux for my seafood gumbo and it is still very quick compared to traditional methods. Roux is just oil and flour so there is no difference in taste. Sounded scary to me at first but is not bad at all.
Unfortunately, I don’t have access to my notes to tell the details of how I do it but I’m sure you could search for directions.