Toss the beef cubes with the flour, salt, and black pepper in a bowl until evenly coated. Place the coated beef in the bottom of the slow cooker.
Add the diced onion, sliced carrots, minced garlic, harissa paste, tomato paste, and ground cumin on top of the beef. Pour in the beef broth and stir gently to combine everything.
Cover and cook on low for 7 to 8 hours until the beef is fork-tender and the gravy has thickened. Stir in the drained chickpeas during the last 30 minutes of cooking so they warm through without becoming mushy.
Ladle the stew into bowls and sprinkle with the chopped cilantro before serving.