In a medium bowl, whisk together the mustard, canola oil, garlic, sugar and chopped rosemary. Place the pork roast on top of a rack fitted in a roasting pan. Place the 2 rosemary sprigs underneath the pork. Sprinkle the roast well with salt and pepper. Using a brush or hands, completely coat the roast with the mustard and garlic paste.
Place the roast in the oven and roast until the internal temperature reaches 145 degrees F, 2 1/2 to 3 hours. Remove from the oven, cover loosely with foil and allow to rest for 15 minutes before slicing. (Reserve 1 cup sliced pork for another use, such as Round 2 Recipe Open Faced Roast Pork and Onion Sandwich.) Serve the sliced pork with the pan drippings poured over top.