The cooking times for roasting beef depend on the size of the piece of meat and whether you prefer the meat rare, medium or well done. Because beef can be eaten rare, it is one of the more foolproof meats to roast, whichever method you choose. It also requires little preparation or supervision during roasting to get excellent results. A meat thermometer will help you determine when the meat is ready.
Types of Beef
Certain cuts of beef--bone in and boneless--are suitable for oven roasting. Suitable cuts of meat include the tenderest parts of the cow that will cook well with dry heat to result in tender, tasty meat. Most supermarket packaging will state whether the cut of beef is suitable for roasting, and a butcher can advise you on the best cuts to use. Generally, a joint labelled with a name that includes "rib," "sirloin," "tenderloin" or "fillet" will be suitable. Joints labelled "chuck," "rump," "round" or "flank" can be dry roasted only if they are prime grades; otherwise, they will be too tough. Before roasting, remove the meat from the refrigerator and allow it to reach room temperature. Season the joint any way you want, and place it on a rack or just set it on the bottom of a roasting tin and leave it uncovered. Note the weight so you can calculate the approximate cooking time.
Constant Heat Method
The constant high-heat method of roasting beef is the easiest because you do not have to adjust your oven's temperature, and aside from basting the meat occasionally, you can just leave it alone to cook. Preheat the oven to 176 degrees C and leave it at that temperature throughout the cooking process. Cook the meat for 18 to 20 minutes per pound for medium-rare. If you use a meat thermometer, the meat will be rare at an internal temperature of 60 degrees C and well done at 170. You can also stick a skewer into the meat and examine the internal juices: red juice means the meat is rare, pink juice means it is medium-rare, and if the juices are clear, it is well done. As an alternative you can use a constant low heat for a longer period of time, but the oven must be at least 135 degrees C to kill any bacteria. The oven will remain at a constant temperature throughout the roasting. Regular basting will prevent the meat from drying out.
Changing Heat Method
This method involves a short burst of high heat at the beginning of the roasting process followed by roasting at a lower temperature. Proponents of this method say that this will result in a tasty outer crust on the joint that helps keep the juices inside the meat while it continues to cook. To roast beef using this method, start by preheating the oven to 246 degrees C. When the oven has reached that temperature, put the joint in the oven for 20 minutes. After 20 minutes, turn the oven's temperature down to 190 degrees C and cook the meat for 15 minutes per pound for rare beef. For medium-rare meat, add 15 minutes; add another 15 minutes for well done. Baste the joint with the juices from the pan throughout the cooking process. Some recipes suggest basting every 15 minutes, but opening the oven that often will affect its temperature, so every 20 to 30 minutes should be enough.