Baked Beef Tenderloin Recipe

Combine marsala, onion, olive oil, vinegar, salt and pepper in a gallon size zip lock bag. Place the tenderloin in the bag and seal. Marinate in the refrigerator for 8 hours, turning occasionally. Remove tenderloin from marinade and place on a rack in a roasting pan. Discard marinate. Bake uncovered at 425° for 45-50 minutes. Check temperature with meat thermometer after 40 minutes: 140° = medium rare, 150° = medium. Remove from oven and let rest 10-15 minutes before slicing and serving.