How to Make It
In a small skillet, combine the cumin, peppercorns, cardamom, cloves and chile and toast over moderate heat for 1 minute. Transfer to a spice grinder and let cool. Grind to a powder and transfer to a large bowl. Finely grind the cashews. In the bowl, mix the spices with the cashews, wine, mace, 1 cup of the yogurt and the juice of 1 lemon. Season with salt. Stir in the lamb and refrigerate for 1 to 2 hours.
Cut half of the mango into 1/3-inch dice and coarsely chop the rest. In a food processor, coarsely puree the cilantro, mint, shallot, garlic and coarsely chopped mango with the remaining yogurt and lemon juice. Transfer the chutney to a bowl. Stir in the diced mango and season with salt.
Light a grill. Thread the lamb onto eight 8-inch skewers. Brush with oil and grill over a hot fire until medium rare, about 3 minutes per side. Serve at once with the mango chutney.