• Preheat the oven to 400 degrees F. Set the oven rack in the middle position.
• Trim the extra fat from the pork tenderloin and cut off the silver skin. Pat dry with paper towel.
• In a small bowl, stir together the rosemary, garlic powder, salt and pepper. Add the olive oil and stir to form a liquidy paste.
• Rub the paste all over the pork tenderloin.
• Heat a large ovenproof nonstick skillet over medium-high heat. Sear the pork on all sides, about 5 minutes total.
• Transfer the skillet (with the pork) to the oven. Cook for about 7 minutes, then brush the tenderloin with 2 tablespoons of the glaze. Cook until the pork reaches an internal temperature of 145 degrees F, an additional 7 to 8 minutes. Cooking time will vary dependent on size and thickness of the tenderloin.
• Serve with the remaining glaze and garnish with minced parsley.

The glaze:

• In a small saucepan, whisk together the maple syrup, water, balsamic vinegar, soy sauce and cornstarch.
• Set over medium heat. Bring the mixture to a simmer, whisking frequently. Continue to simmer until the glaze thickens slightly, 3 to 4 minutes.
• Set aside 2 tablespoons of the glaze for basting the tenderloin parway through cooking.