Season meat with salt and pepper. Place meat, fat side up, in a 15-1/2x10-1/2x2-inch roasting pan. Insert an oven-going meat thermometer into center of roast, making sure it doesn't touch bone. Roast, uncovered, in a 350 degree F oven. For medium rare, roast for 1-3/4 to 2-1/4 hours or until meat thermometer registers 135 degrees F. Cover with foil; let stand 15 minutes. Temperature of meat after standing should be 145 degrees F. (For medium, roast for 2-1/4 to 2-3/4 hours or until meat thermometer registers 150 degrees F. Cover; let stand 15 minutes. Temperature of meat after standing should be 160 degrees F.)
Meanwhile, prepare Oven-Browned Potatoes or Yorkshire Pudding.
Makes 12 to 16 servings.
After removing meat from the oven, increase oven temperature to 450 degrees F. Measure pan drippings. If necessary, add enough cooking oil to drippings to equal 1/4 cup; return to pan. In a mixing bowl combine eggs and milk. Add flour and salt. Beat with an electric mixer or rotary beater until smooth. Stir into drippings in roasting pan. Bake for 20 to 25 minutes or until puffy and golden. Cut into 12 squares. Serve at once with roast.
In a small bowl, combine sour cream, horseradish, and salt. Cover and chill until ready to serve.
Peel potatoes; cut into quarters. Cook in boiling salted water for 10 minutes; drain. About 30 to 40 minutes before roast is done (the roast temperature should be about 100 degrees F), arrange potatoes around roast, turning to coat them in drippings. Serve potatoes with the roast.