Cut roast in half; sprinkle with Cajun seasoning. In a large skillet, brown roast in oil on all sides. Transfer to a 5-qt. slow cooker. Combine the tomatoes, red pepper, celery, onion, tapioca, garlic and salt; pour over roast. , Cover and cook on low for 6-8 hours or until meat is tender. Serve with rice. , Freeze option: Remove beef, vegetables and juices from slow cooker; cool slightly. Slice beef; transfer all to freezer containers. Freeze for up to 3 months. To use, thaw in the refrigerator overnight. Place in a Dutch oven; heat through. Thin with beef broth if necessary. Serve with rice.