Place the stew meat in the slow cooker and sprinkle it with Cajun seasoning, salt, and black pepper. Toss to coat the pieces evenly.
Add the diced onion, green bell pepper, celery, and minced garlic on top of the meat.
Pour in the diced tomatoes and beef broth.
Add the cubed potatoes, sliced okra, and cayenne pepper.
Stir everything once to combine, then cover and cook on low for 8 hours until the beef is tender and the potatoes are soft.
Taste and adjust salt or cayenne if needed before serving.