Pre-heat oven to 180C/350F/Gas 4.

Combine applesauce, honey, Dijon mustard, and rosemary leaves in a small bowl and stir to combine. Season with salt and black pepper, to taste, and set aside.

Heat coconut oil in a large oven-safe skillet over medium heat.

Generously season the pork with salt and black pepper, to taste. Cook until browned and evenly seared on all sides, approximately 5-10 minutes.

Remove from the heat and spread half of the applesauce mixture all over the top and sides of the pork. Arrange the chopped apples around the sides of the pork and place the skillet in the preheated oven.

Roast for 20 minutes, then remove from oven and flip the pork. Brush with remaining applesauce mixture and return to the oven for another 20-25 minutes, or until the pork is cooked through. To test for doneness, use an instant-read thermometer and insert it into the thickest part of the tenderloin. It should read just below 145F (63C) - the temperature will rise several degrees while the meat rests. If you don't have a thermometer, insert a skewer into the thickest part of the pork and the juices should run clear.

.Remove from oven and cover loosely to rest for 5 minutes before serving. Enjoy!