We don't recommend cooking this roast past medium. Open the oven door as little as possible and remove the roast from the oven while taking its temperature. If the roast has not reached the desired temperature in the time specified in step 3, heat the oven to 225 degrees for 5 minutes, shut it off, and continue to cook the roast to the desired temperature. For a smaller (2 1/2- to 3 1/2-pound) roast, reduce the amount of kosher salt to 3 teaspoons (1 1/2 teaspoons table salt) and black pepper to 1 1/2 teaspoons. For a 4 1/2- to 6-pound roast, cut in half crosswise before cooking to create 2 smaller roasts. Slice the roast as thinly as possible and serve with Horseradish Cream Sauce (see related recipe), if desired.