Remove roast from package; pat dry with paper towels. Leave string netting on roast.
In a small bowl, mix together the basil, oregano, garlic powder, onion powder, salt, and pepper. Stir in the olive oil and make a paste.
Rub spice mix over the entire roast and place on a roasting rack in a roasting pan.
Place slices of butter on top of roast.
Bake, uncovered for 1 ¾ to 2 hours, or until a meat thermometer inserted in center of roast reaches 175 degrees F.
Cover roast with foil and let stand at least 10 minutes before removing string netting and carving.
Notes
Expert Tips
Keep the Mesh: Don't remove the mesh string around the boneless turkey roast; it helps the meat keep its shape during cooking.
Use a Meat Thermometer: For a foolproof turkey, get a meat thermometer. To check for complete cooking, insert it into the thickest part of your turkey roast. The internal temperature should reach 165°F (74°C).
Allow Time to Rest: After cooking, let the turkey rest for 10-15 minutes. This allows the meat juices, which rise to the surface during cooking, to redistribute throughout the roast. Skipping this step will result in a less juicy turkey when sliced.