This is a recipe from Epicurious which I modified for a single tenderloin.
• 1 pork tenderloin – about 1lb or a tad more
• 5 or 6 thin slices prosciutto (each about 6 x 2 inches)
• ½ cup fresh breadcrumbs made from crustless French bread
• 2 teaspoons chopped fresh rosemary
• 2 teaspoons chopped fresh thyme
• 2 tablespoons olive oil
• 1 teaspoon salt
• 1 teaspoon freshly ground black pepper
• ¾ - 1 lb mushrooms, sliced
• 1 garlic clove, minced
• 1 cup dry white wine
• 1 cup chicken broth
1. Place the tenderloin on a work surface and remove fat and the “silver” skin.
2. With a sharp knife make a slit in the center cutting almost through but not quite so the tenderloin can be butterflied.
3. Slightly overlap prosciutto strips down the length of the pork.
4. Place the bread crusts, 1 teaspoon rosemary, and 1 teaspoon thyme into the Oscar and pulse a few times.
5. Add 1 tablespoon oil and pulse to blend.
6. Sprinkle this crumb mixture on top of the prosciutto.
7. Using kitchen string, tie the tenderloin closed in about five places along the length while keeping the slit closed with your fingers.
8. Place the tenderloin in a roasting pan.
9. Mix salt, pepper, 1 teaspoon rosemary, and 1 teaspoon thyme in a small bowl and moisten slightly with a few drops olive oil.
10. Rub this herb mixture over the outside of the roast.
11. Let stand 30 minutes.
12. Preheat oven to 350°F.
13. Add a couple of tablespoons olive oil in the roasting pan and sauté the tenderloin over medium-high heat until browned on all sides.
14. Place the roast in the oven.
15. Roast pork until thermometer inserted into thickest part of pork registers 145°F, about 35 minutes.
16. Transfer roast to platter; tent loosely with foil to keep warm (temperature will rise 5 to 10 degrees as pork stands).
17. Place the roasting pan and meat juices over medium heat.
18. Add mushrooms to the pan.
19. Sauté these until they begin to brown, about 5 minutes adding a couple of dabs of butter if the mushrooms seem to be drying.
20. Add the garlic and continue the sauté for another minute.
21. Add the wine and the broth.
22. Boil until sauce thickens enough to coat spoon, scraping up browned bits, about 12 minutes.
23. Season with salt and pepper.
24. Cut roast crosswise into 1/2-inch-thick slices; serve with mushroom sauce.