Remove roast from refrigerator and allow to rest at room temperature. Preheat oven to 350°F.
Using a brush or spatula (or your hands), cover entire roast (leave the roast tied) with mayonnaise. Sprinkle all sides with salt, pepper, and poultry seasoning if using.
Place in a roasting pan (if there is skin, place skin side up). Bake uncovered in a roasting pan for 30-35 minutes per pound, until the internal temperature reaches 160°F using a digital thermometer.
Remove roast from the oven and lightly tent with foil. Rest for 10-15 minutes, until roast reaches 165°F. Carefully remove string (kitchen scissors work well for this), slice, and serve.
Notes
Mayonnaise seals the juices in the roast and basting is not required. It does not leave a taste.
Estimate ½ pound (or more) per person.