I'm gonna start with my sister's recipe. It's semi-commercial in nature, used for feeding a BIG crowd, like a wedding reception dish or a basic Noo Awlins Friday night party. (Grin!) *Half* this recipe will still FILL a 12-qt. stockpot.
¼ c EVOO
4 onions (chopped fine)
2 bell pepper (Chopped fine)
1 celery (chopped fine)
3 garlics (entire garlic, not just 3 toes) (chopped fine)
2 bunches shallots (green onions) (chopped fine)
1 #10 can tomatoes (diced) (about 6 lbs.)
3 c tomato puree
2 sticks (1/2 lb.) butter
1 c parsley
A few Bay leaves
Creole seasoning (Zatarain's, Tony Chachere's, etc.)
Hot sauce (
Frank's, etc.) Tabasco
10 c converted/instant rice
4 lbs. sausage (andouille, boudin, etc.)
5 lbs. peeled shrimp
Heat olive oil in big pot (preferably cast iron). Add butter, onion, garlic, and celery. Cook til soft. Add tomatoes and tomato puree. Simmer 10 minutes. Add seasonings. Simmer 5 min. Add sausage. Simmer 10 min. Add water (fill the #10 can), return to boil. Add shrimp, return to boil. Correct seasonings. Add rice, return to boil, then lower heat to simmer. 10 min. Do not uncover during this time. Add green onion, bell pepper, parsley, and Bay leaves. Re-cover. Simmer 10 min. Stop heat. Let sit for 15 min before serving.
That's basic jamba. With that as a starter, you can see how you could manipulate the ingredients: fresh tomatoes instead of canned, stock instead of plain water, different rice, etc.
I have heard of people who use a roux for a jamba base. If you wanna go that route, I'd recommend a light roux rather than a dark one. I personally don't see any need for that density or flavor in jambalaya.