Step 1: Prepare Ingredients: Rinse and soak dried red beans overnight (skip if using canned). Dice onion, bell pepper, celery, and mince garlic. Slice Andouille sausage into ½-inch pieces.
Step 2: Sauté Aromatics and Sausage (Optional but Recommended): In a skillet, heat olive oil or butter over medium heat. Sauté onions, bell peppers, celery, and garlic for 3-4 minutes until softened. Add sliced sausage and cook for another 2-3 minutes until lightly browned.
Step 3: Assemble in Slow Cooker: Transfer sautéed vegetables and sausage into the slow cooker. Add soaked or canned red beans. Pour in chicken broth and stir in Cajun seasoning, smoked paprika, thyme, black pepper, salt, and cayenne. Add bay leaves.
Step 4: Slow Cook: Cover and cook on low for 6-8 hours or high for 4-5 hours, until beans are tender and creamy. About 15 minutes before serving, remove bay leaves and stir to combine.