Method
Place the lamb and pork pieces in a large bowl that has been rubbed with the garlic clove. Season with salt and pepper, and toss.
In a saucepan, heat the oil. Add the onions and saute for 5-6 minutes, then add the curry powder and garlic. Saute for another minute. Add the sugar, tamarind paste, vinegar, and jam and stir well. Stir the cornstarch mixture and add it to the onions, and cook, stirring constantly, until it thickens. This should take about 3 minutes. Cool, then add to the meat and toss well. Marinate for up to 2-3 days.
One day before preparing the sosaties, combine the dried apricots and sherry in a small bowl, cover, and let sit overnight in the refrigerator.
Drain meat from sauce and reserve. Thread lamb, pork, and apricots on skewers. Grill until browned on all sides. In the meantime, heat sauce until it boils. Simmer and let cool slightly. Serve skewers on plate with heated sauce.