Step by step

1. Gather the ingredients.
2. In a small shallow bowl, combine the apple cider, nutmeg, and curry powder and set aside.
3. In a small microwave-safe dish, combine the butter, onion, and garlic. Microwave on high for 1 to 2 minutes or until the onion is softened. Place this mixture in the bottom of a 3- to 4-quart slow cooker.
4. Dip each chicken breast into the reserved apple-cider mixture to coat and then place them in the crock pot over the onion mixture. Pour any remaining apple-cider mixture over the chicken. Add salt and pepper to taste.
5. Cover the slow cooker and cook on low for 5 to 6 hours or until the chicken is almost cooked. Add the sliced apples and cook for 40 to 50 minutes longer on low or until the apples are tender and the chicken is thoroughly cooked to 165 F as measured by a reliable meat thermometer.
6. Remove the chicken and apples to a serving plate and cover with aluminum foil to keep warm.
7. To make the sauce, whisk together the vinegar, broth, and cornstarch in a small bowl until well mixed and lump free and stir into the liquid in the crock pot. Cover and cook on high heat, stirring occasionally, until sauce is thickened and bubbly, about 10 to 15 minutes. Pass the sauce separately at the table.
8. Enjoy!