In a large skillet, brown the sausage over medium heat. Drain off any excess grease.
Transfer the sausage to the slow cooker. Add the onion, celery, and bell pepper to the skillet and cook until softened, about 5-7 minutes.
Add the garlic, cayenne pepper, smoked paprika, thyme, and black pepper to the skillet and cook for 1 minute more.
Transfer the vegetables to the slow cooker. Add the chicken broth, red kidney beans, and bay leaf.
Cover and cook on low for 6-8 hours or on high for 3-4 hours.
Remove the bay leaf before serving. Serve hot.