Pork has just about replaced beef and chicken in my list of favorite dishes and who doesn't love a good pork roast? The balsamic vinegar and the rosemary give this meal that special oomph!
In a food processor, combine leaves, garlic, oil, vinegar, salt, and pepper, and pulse to make a coarse, wet paste, scraping down the bowl as necessary. Spread 3/4 of the paste on all sides of roast. Place roast, fat side up, in a shallow roasting pan large enough to hold roast with 3 inches room around all sides. Roast 15 minutes in a preheated 450º oven.
Meanwhile, combine potatoes and remaining paste in a large bowl. Reduce oven to 350º. Add potato mixture to pan, arranging potatoes around the roast. Continue roasting 60 minutes, tossing potatoes halfway through, or until internal temperature of roast reaches 155º F and potatoes are tender. (If roast is done before potatoes, transfer it to a cutting board and return roasting pan with potatoes to oven.)
Remove roast from oven and let rest 10 minutes. Slice roast and arrange on platter. Surround with potatoes and serve.