1. Preheat oven to 225ºF. Place roasting rack in large roasting pan.
2. Sprinkle top round roast with salt and papper. Heat a large skillet over medium-high heat. Add oil and top round roast to pan; sear for 5 minutes, turning to brown on all sides. Remove roast from pan.
3. In small bowl, combine horseradish, parsley, thyme and garlic. Evenly spread horseradish misture over top round roast. Place onion disks on roasting rack in roasting pan. Place to round roast on top of onion disks.
4. Roast for 3 to 3-½ hours or until internal temperature reaches 135ºF for medium-rare. Transfer roast to cutting board; let stand 10 minutes before slicing (internal temperature will rise 5 to 10ºF upon standing*).
Approximate nutritional values per serving:
Calories 370, Fat 12g (3g Saturated), Cholesterol 160mg, Sodium 890mg,
Total carbohydrates 4g, Fiber 1g, Protein 64g
If you don't have a skillet large enough to brown the whole roast at once, cut it into halves or thirds and brown each piece separately.
*For food safety, the internal temperature of the roast should reach a minimum of 145ºF.
Prep: 20 minutes
Cook Time: 3 hours 30 minutes