Cooking a sirloin tip roast in the oven keeps the meat moist, tender, and to your desired level of doneness. A 4 lb. roast will feed around six to 10 people, depending on the serving sizes.
Set the sirloin tip roast out at room temperature for two hours so that it cooks evenly.
Place the roast on a roasting rack inside a roasting pan to keep it from sitting in its own juices.
Heat the oven to 350 degrees Fahrenheit.
Coat the sirloin tip roast lightly with vegetable oil so that the seasonings will stick. Rub the seasonings into the meat with your fingers.
Bake the roast in the preheated oven for 2 ½ to 3 ½ hours or until the meat reaches 130 to 135 degrees Fahrenheit for a medium-rare meat. Cook the roast to a temperature of 120 to 125 degrees for rare meat, 145 to 150 degrees for medium and 155 to 165 degrees for well-done.
Remove the roast from the oven. Place the roast on a serving platter and allow it to cool for 15 to 30 minutes before cutting.