1. Season pork all over with salt and pepper and place in a large resealable bag or large bowl. In a small bowl, stir maple syrup, mustard, and rosemary until blended; add to pork, then turn pork to coat. Seal bag or cover bowl and refrigerate at least 4 hours and up to 2 days, turning pork in marinade occasionally.
2. Center a rack in oven and heat to 325 degrees. Line a rimmed baking sheet or roasting pan with foil and set a rack inside.
3. Place pork on rack with fat cap facing up. Gently pat dry to remove excess moisture, leaving as much mustard and rosemary on roast as possible. Transfer to oven and roast until pork is very tender throughout and center registers 190 degrees, about 4 hours. Remove from oven and let rest at least 10 minutes before slicing against the grain.
Source: Hannaford fresh Magazine, December 2020