Transfer to preheated oven and roast for 50 minutes or until internal temperature is about 150˚F (65˚C).
Remove and allow pork loin to rest for 10 minutes before carving and serving with creamy horseradish sauce.
Creamy Dijon Mustard Sauce
Melt butter in a small saucepan. Add all-purpose flour. Stir for 2 to 3 minutes until light brown. Pour in milk whisking vigorously to dissolve the flour into the milk until smooth.
Stir in Dijon mustard, salt, and pepper. Cook until sauce is thick and bubbly. Turn off stove.