1 Put The Fennel Seeds, Peppercorns, Thyme And Rosemary Leaves, Garlic And 2 Teaspoons Salt Into A Spice Grinder Or Coffee Grinder And Grind To A Paste. Alternatively, You Can Pound The Mixture With A Mortar And Pestle. Put The Mixture Into A Bowl And Stir In 2 Tablespoons Olive Oil. 2 Rub The Mixture Evenly All Over The Pork Shoulder. If The Roast Is Tied, Untie It To Rub The Inside With The Rub Mixture As Well, Then Retie It. Wrap The Roast Tightly In Plastic Wrap To Hold The Rub Against The Skin And Marinate Overnight (Or Up To Two Days). 3 Peel, Halve, And Core The Apples. Cut Each Apple Half Into About 4 Wedges. Peel The Onions. Cut In Half From Tip To Root. Trim The Root And Tip. Cut Each Onion Half Into About 12 Thin Wedges. Put The Onions And The Apples Together In A Bowl And Toss To Mix. 4 Preheat The Oven To 450