1. Heat broiler, with rack set 4 inches from heat. On a broilerproof rimmed baking sheet, rub pork with 1 tbsp oil; generously season with salt and pepper. Broil, until pork registers 145 degrees on an instant-read thermometer, 12-14 minutes. Transfer to a plate, cover loosely with aluminum foil, and let rest, 10 minutes (temperature will rise about 5 degrees as it sits).
2. Meanwhile, in a large skillet, heat remaining tbsp oil over medium heat. Add leeks and fennel seeds; cook stirring occasionally, until leeks are tender, about 6 minutes. remove from heat; stir in honey and vinegar, and season with salt and pepper. Thinly slice pork, and serve with apples and leeks.