01 - Preheat the oven to 180°C (350°F).
02 - In a bowl, combine Dijon mustard, honey, olive oil, salt, and black pepper until smooth.
03 - Coat the pork roast evenly on all sides with the mustard marinade.
04 - Place the carrots, potatoes, and onion in a roasting dish and set the seasoned pork roast in the centre.
05 - Roast in the oven for about 1 hour and 30 minutes, occasionally basting the pork with pan juices.
06 - Test the doneness by ensuring the pork's internal temperature reaches 70°C (160°F) with a meat thermometer.
07 - Let the pork rest for 10 minutes before slicing and serving.