First Step: Prepare Ingredients
Chop the onion, celery, and green bell peppers into bite-sized pieces. Dice the garlic finely. Slice the Andouille sausage into 1/4-inch thick pieces, and cut the chicken breasts into 1-inch cubes. Measure out Creole seasoning, oregano, and other spices.

Second Step: Brown the Sausage (Optional)
For deeper flavor, lightly brown the Andouille sausage in a skillet over medium heat along with onion, celery, and bell peppers until caramelized and aromatic, about 5-7 minutes. Then transfer these ingredients to the crockpot. This step is optional but highly recommended for a richer jambalaya flavor.

Third Step: Combine Ingredients in Crockpot
Add the browned sausage and vegetables (or raw if skipping step two) into the crockpot. Add diced tomatoes with juice, chicken broth or seafood stock, chicken pieces, Creole seasoning, oregano, kosher salt, and diced garlic. Stir everything gently to combine evenly.

Fourth Step: Slow Cook the Jambalaya
Cover and cook on low for 7 to 8 hours or on high for 3 to 4 hours until the chicken is cooked through and vegetables are tender. Stir halfway through cooking to ensure even flavor distribution, if possible.

Fifth Step: Add Shrimp
About 30 minutes before serving, add the peeled and deveined shrimp to the crockpot. This prevents them from overcooking, ensuring they remain tender and flavorful. Cover and continue cooking until the shrimp turn pink and opaque.

Sixth Step: Prepare Rice
Approximately 20 minutes before serving, cook the rice separately. Boil 3 1/2 cups of water, add rice, cover, reduce heat to low, and simmer for 18-20 minutes without lifting the lid. Fluff with a fork once done.

Final Step: Combine and Serve
Stir the cooked rice into the crockpot jambalaya gently, allowing it to absorb extra liquid for 5 minutes. Taste and adjust seasoning as needed. Serve hot, garnished with chopped fresh parsley. Consider pairing with cornbread, fried okra, or a fresh side salad for a complete meal.