Try this marinade recipe for an incredibly flavourful and beautifully browned roast beef.
Pierce roast all over with fork. Combine soy sauce, honey, pepper sauce, lime juice, cumin and oyster sauce (if using) in large sealable freezer bag. Place roast in bag with marinade; refrigerate for 12 to 24 hours. Discard used marinade.
Place drip pan containing 1/2 inch (1 cm) water under grill. Preheat barbecue to medium-high (400°F/200°C).
Insert meat thermometer into middle of roast. Place roast on grill over drip pan that is moved to one side; turn heat off under just the roast. Cook at constant heat, in closed barbecue, until thermometer reads 155°F (68°C) for medium, about 1 hour and 30 minutes.
Remove roast to cutting board; cover with foil for 10 to 15 minutes. Carve across the grain into thin slices.