Add sliced portabello mushrooms, or even just quartered white mushrooms too...
Cajun Red Beans requires an overnight soak of the beans (1-2lbs). Other ingredients include yellow/white onions, galic, black & red pepper, parsley, celery, 3 bay leaves, and some kind of meat. For those without hypertension issues, you'll also need salt. Traditionally, that would be some kind of salted or pickled pork, perhaps some kind of sausage (usually smoked and/or hot). I gravitate towards sausage, but to be healthier, I've started using hand-sized slabs of ribs that I've smoked or oven-baked, seasoned without salt.
You'll also need rice to serve them over.
Chop your onions & sautée them in butter to soften/clarify them, along with your garlic in your big pot. Then add your meat cut for the pot (slices if sausage, or single ribs) Add your beans, chopped celery, and spices with enough water to cover them. Bring the pot to a rolling boil, for a few minutes, then stir thouroughly and turn to low. Stir pot occasionally to prevent from burning.
After a while- an hour or so in a standard pot, shorter if using a pressure cooker- crush about a spoonful of the beans against the side of the pot- this will release their starches into the pot and will make your beans creamy. When the beans are all soft, the pot is creamy (and the meat is starting to fall off the ribs, they're basically done.