Preheat your oven to 350 degrees F and light your barbecue about 40 minutes later.
To make your marinade, grind the cumin seeds, fennel seeds and cloves in a pestle and mortar with some salt and pepper. Chop the thyme and rosemary leaves, orange zest and garlic together finely. Put into a bowl with the ground spices, then add the rest of the marinade ingredients and mix together.
Rub your chosen meat all over with the marinade, really getting it into all the nooks and crannies and, in case of the lamb, the slashes. Place the meat in a snug-fitting roasting pan, top with any leftover marinade and cover loosely with aluminum foil. Bake the meat in the preheated oven until sweet and tender. This will take 1 1/2 hours for the pork ribs and the lamb (but if you like your lamb pink, it will only need 1 hour), and 1 hour and 20 minutes for the chicken.
Now you're going to finish your meat on a medium hot barbecue. Place it carefully on the bars of the barbecue and sear it well on 1 side, then turn it over. While it's cooking, use your reserved rosemary sprigs to baste the meat with the sticky juices from the bottom of the roasting pan. Keep turning and brushing the meat until you've built up a lovely sticky, charred crust, then take it off the barbie and rest it on a serving dish for a few minutes. Meanwhile, pop your roasting pan on the barbie or over a gas burner and let the juices reduce a bit.
Cut the pork into individual ribs, carve the leg of lamb into slices or tear the chicken into pieces, and serve with a bowl of the lovely marinade juices from the roasting pan.
Recipe Excerpted from JAMIE AT HOME by Jamie Oliver. Copyright (c) 2008. Published in the U.S. by Hyperion. All Rights Reserved. Available wherever books are sold. www.jamieoliver.com