Jambalaya in casing

I was thinking of doing the same thing with chili and rice.

Have done this. You need to make sure it's done with the quickness as rice will be the first thing to spoil if it "sits out" after being cooked. Essentially, you would need to immediately quick chill and or soft freeze the amount you want to grind into casings right after it is cooked. You should be able to determine how much you typically have left over for this. As far as the taste, mine was a bit dry, so possibly adding some fat would have helped.

Your Jambalaya will be fully cooked. If making a "sausage" out of it, you will need to add a binder (uncooked meat) to the blend before casing it.

Sounds interesting. Do photos.