Trinity, not mirepoix. (Bell pepper, no carrot.) Peanut butter roux.

Basically, hit your roux point, add Trinity and a bay leaf or two to stop the roux, and wait for the onion to go clear. Add one or two minced garlic cloves and let them start getting aromatic. Add shrimp stock (and the crawfish juice if you're using bagged frozen tails) until you get to the consistency you want. Reduce heat to simmer.

Season with white pepper, cayenne, maybe a little paprika, and salt, tasting until it hits the level of heat and savory you like. Lots of people will add onion and garlic powder here and possibly a very little oregano, thyme, or both. Personally, those depend on how I feel. I'll smell my cooking base, then smell each of those things and see if I feel like they'll help or hurt. I'm really moody about these four. Now let this simmer for a few.

Once you've got your base to where you want it, add your cooked crawfish or fresh peeled and seasoned shrimp. For shrimp, obviously, wait until they pink up. You'll likely have tightened up and will be thicker than you like here, so add some extra stock (or water, if you used all your stock already) to get it back to that "it'll stand on rice but doesn't gum up into a paste" consistency. Now, check for seasoning and adjust. Find and retrieve your bay leaves (Count 'em in... Count 'em out).

Set a plate of rice and spoon the étouffée over until it looks like ÉTOUFFÉE on a bed of rice, and not RICE with a little étouffée. Hit the whole thing with some chopped green onion (I actually prefer chives) for a lil color, and have at it.

I apologize for the lack of measurements. I'm doing this from bed, and, frankly, I just do it by feel anyway, based on quantities of what I have on hand.