Preheat oven to 400 degrees F. Coat a shallow roasting pan with cooking spray.
Using a sharp knife, cut pork lengthwise 3/4 of the way through. Place in a prepared pan and spread sun-dried tomato pesto in the incision. Fold pork back in half and use a metal or wooden skewer to close the seam. Season with salt and black pepper.
In a small bowl, combine vinegar, honey mustard and thyme. Spoon mixture over pork.
Roast 45 minutes, until an instant-read thermometer reads 155 degrees F (pork may still be pink in the center and that's O.K.).
Let pork rest for at least 10 minutes before slicing crosswise into 1-inch thick slices. Serve about 1/2 of the pork with 2 cups rice. Reserve remaining rice and pork for additional meals.
