Heat oven to 350 degrees F. Pat beef dry and spread with butter. Sprinkle with salt and pepper and place on wire rack set in rimmed baking sheet. Roast at 350 degrees for about 35 to 45 minutes or until instant-read thermometer registers 135 degrees, flipping roast halfway through cooking.
While roast is cooking, stir together blue cheese, butter and parsley in a small bowl; refrigerate until ready to use.
Remove roast to a serving platter and top with 1/3 of the blue cheese butter. Tent with foil and let roast rest for 10 minutes. Slice and serve with remaining butter. Makes 8 servings.