A whole beef fillet is a premium roast best suited for dry-heat cooking methods like grilling. One of the tenderest pieces of meat on the cow, it goes by other names including beef tenderloin roast. Grilling is a popular method of cooking. In fact, according to information from the Arizona Beef Council, over 32 percent of American households reported eating grilled food at least once every two weeks, year-round.

Prepare your whole beef fillet for grilling. Leave it in the refrigerator until about one hour before you put it on the grill. Season it and then place it covered in a cool place out of the sun to bring it to room temperature.

Season your whole beef fillet with a dry rub to add flavor about one hour before cooking. Mix salt and pepper together for the most basic dry-rub recipe. Purchase a pre-made dry rub or take advantage of this opportunity to add a personalized touch to your dish. Common ingredients for a dry rub include herbs and spices like parsley, garlic and freshly ground pepper. Add sweetness to your dry rub with brown sugar. Make your dish spicy by adding chili powder to the mix. Massage the fillet with your fingertips to completely cover it in the dry rub.

Cook with a gas grill and leave the primary burner on high, but turn off all other burners. Insert a meat thermometer into the side so you can turn the meat over without disturbing it. Put the whole beef fillet on the grate over the cool part of your gas grill and close the lid. Turn occasionally.

Grill your whole beef fillet on a charcoal grill. Allow the coals to burn for about 30 minutes on medium-high heat and then pile them evenly on one side. Open your grill vents and place the meat on the grate on the cool side of the grill. Reduce the temperature by adjusting the vents. Put the lid down, but turn occasionally.

Cook the whole beef fillet for about 25-30 minutes or until the thermometer reads 5 degrees Fahrenheit less than the desired final temperature, which is 125-130 degrees for rare, 135-140 degrees for medium rare, 140-150 degrees for medium, 150-155 degrees for medium well and 160-165 degrees for well done.

Take the meat off the grill and place it on a cutting board. Make a loose tent with aluminum foil and place it atop the roast for 20 to 30 minutes to retain the juices and make it easier to cut. Remove the thermometer before serving.