This slow cooker French onion chicken recipe is simple and flavorful. Just add chicken, French onion soup mix, vegetables (like carrots, potatoes, and celery), and chicken broth to the slow cooker. Cook on low for 6-8 hours or high for 3-4 hours. Optional ingredients like mushrooms and fresh herbs can be added for extra flavor. Season with salt and pepper, and enjoy a delicious, easy meal!