Rosemary Maple Pork Tenderloin

1. Remove the ends and peel from the shallot; chop finely. Preheat a large sauté pan on medium-high for 2 to 3 minutes. Season pork with salt and pepper. Place oil in the pan; swirl to coat. Add pork; cook for 4 to 5 minutes, turning occasionally, or until well browned. Remove pork from pan; cover to keep warm.
2. Remove pan from heat and add marsala. Stir in mushrooms and shallots; cook for 2 to 3 minutes over medium-high heat, stirring often, or until wine has completely evaporated.
3. Stir in beef stock, syrup, and whole rosemary sprigs. Return pork to pan; cover and cook for 10 to 12 minutes, turning pork occasionally, or until internal temperature of pork reaches 155°F. Use a meat thermometer to accurately ensure doneness. Remove pork from the pan and transfer to a cutting board. Let pork stand for 5 to 10 minutes before slicing. Temperature will rise to USDA-recommended 160°F.
4. Continue to cook sauce for 4 to 5 more minutes or until thickened. Slice pork into 1 inch-thick slices, top with mushroom sauce and serve.