Marinade: whisk together the orange juice, soy sauce, rosemary, and garlic.

Pour marinade over pork tenderloin.

Marinate for at least 1 hour, preferably overnight.

Preheat oven to 400°F.

Drain pork, reserving the marinade.

Season pork with salt & pepper to taste.

Roast until internal temperature is 145°F or higher.

Meanwhile, strain the reserved marinade and bring it to a simmer. Serve as sauce for meat.