Split the pork lengthwise without cutting through it so that you can open it like a book (butterflied). Pound to a uniform thickness of about 1 inch (2.5 cm). Season with salt and pepper. In a small bowl combine the apple, apricots, Parmesan and sage and mix well. Spread over pork, roll pork and tie with kitchen twine at 2 inch (5 cm) intervals. Heat the vegetable oil in a large pan over high heat and brown the pork roast on all sides. Add the potatoes, fennel and garlic, and drizzle the olive oil over all. Roast 35 to 40 minutes in a 400F (200C) oven. Slice across roll to serve. Transfer to warm serving platter along with the potatoes, fennel, and garlic. Garnish with the reserved fennel fronds.