Place roast in a large freezer bag and pour the marinade over the roast.
Close bag and marinate in refrigerator 12 to 14 hours.
Remove roast from refrigerator and pat dry with paper towels.
Discard the marinade.
Preheat oven to 450°F.
Season roast with an additional 2 teaspoons kosher salt and 1 teaspoon black pepper.
Place in a shallow roasting pan fitted with rack.
Roast 15 minutes in 450° oven; reduce heat to 325°F.
Cook approximately 1 hour to reach medium (135-140°F) doneness.
Remove roast from oven, tent loosely with foil and rest 10 minutes before carving in thin slices.
Notes
Storage:The beef roast can be stored in the fridge for up to 3 days in an airtight container.You can also add the marinade and freeze the roast for up to three months in a freezer safe container.Things to know:Expert Tip: You can add the roast in its marinade to the freezer. When you're ready to serve let thaw overnight in the fridge and proceed with the recipe.
If you are short on time, you can marinate the beef for as little as 2 hours. But, this will result in a tougher roast.
The longer the beef roast marinades, the more flavorful it will be. Try up to 24 hours if you have the time.
Using fresh cracked pepper will give this rump roast a deep and rich flavor.
Cook time will vary based on the size of your roast. If your roast is larger or smaller than 3 pounds you will need to adjust the cook time.
Be sure to allow the roast to rest for 10 minutes before carving for best results.
The cook time for this recipe should result in a perfectly medium roast.