Mix salt, pepper, sage, rosemary and orange zest in a small bowl.
Cover your pork tenderloin with this rub then place it in a large resealable plastic bag or wrap it in plastic wrap and refrigerate for at least 6 hours, preferably overnight.
Preheat your oven at 375°F
Add about a teaspoon of olive oil at the bottom of a large non stick pan and heat it over medium-high heat.
When pan is real good and hot, add your pork tenderloin and leave it to sear for 2-3 minutes until a nice golden crust forms, then flip it around and repeat with all four sides.
Transfer your tenderloin to a shallow oven safe dish, cover loosely with foil and cook until internal temperature reaches 145°F (about 20-25 minutes)
Take your tenderloin out of the oven and let it rest for about 10 minutes before to slice and serve.
Serve with cranberry sauce, if desired, and a side of fresh vegetables. Brown or wild rice would also work beautifully with this.
For the cranberry sauce
To make the cranberry sauce, simply mix all the ingredients in a small food processor until well smooth and well incorporated.