Coffee-Braised Roast Beef

Directions

1. In a large shallow dish, combine vinegar and 2 garlic cloves. Add roast; turn to coat. Cover and refrigerate overnight, turning occasionally.
2. Drain roast, discarding marinade. Pat roast dry; sprinkle with salt and pepper. Place roast in a 5- or 6-qt. slow cooker; add coffee, broth, onion and remaining 2 cloves garlic. Cook, covered, on low until meat is tender, 6-7 hours.
3. Remove roast and keep warm. Strain cooking juices, discarding onion and garlic; skim fat. In a small bowl, mix cornstarch and cold water until smooth; gradually stir into slow cooker. Cook, covered, on high until gravy is thickened, about 30 minutes. Slice roast; serve with mashed potatoes and gravy.