Wash vegetables, then peel and quarter the onion; finely chop garlic, trim ends from carrots and cut in half lengthwise; cut potatoes in half.
In a small bowl, mix oil, garlic, herbs, and pepper; rub mixture all over the outside of the roast.
Place vegetables in a 13 x 9 baking dish and place roast on top, fat side up. Cover and refrigerate for one hour.
Preheat oven to 475 degrees. Cover the dish with foil and roast for 20 minutes.
Reduce oven to 425 degrees and continue to cook for another 30-40 minutes. Vegetables should be tender and meat should read a temperature of 145 degrees on a thermometer.
Remove from oven and use foil to tent over the meat and vegetables. Let stand for 20 minutes before slicing.