Preparation Arrange pork tenderloin in one 11 x 7 x 2- inch glass baking dish and lamb in another 11 x 7 x 2-inch glass baking dish. Mix 2 tablespoons brown sugar, 1 tablespoon curry powder, coriander, peppercorns, and salt in small bowl; sprinkle half of mixture over pork and remaining half over lamb and stir. Slice 1 onion and place in medium bowl; add apricots, orange peel, red wine, vinegar, 1/2 cup whipping cream, and oil; stir to blend. Divide onion-apricot marinade between dish with pork and dish with lamb. Cover both dishes; chill at least 4 hours. DO AHEAD: Can be made 8 hours ahead. Keep chilled. Cut remaining onion in half crosswise, then cut each half into quarters. Separate quarters into individual onion layers; set aside. Place large fine-mesh strainer over large saucepan. Add pork mixture to strainer and allow marinade to drain into saucepan. Transfer pork to medium bowl. Repeat with lamb mixture, allowing marinade to drain into same saucepan. Transfer lamb to another medium bowl. Alternate pork cubes, marinated dried apricots, onion pieces, and bacon pieces on metal skewers, beginning and ending with pork. Repeat with lamb cubes, alternating lamb, apricots, onion pieces, and bacon pieces on skewers. DO AHEAD: Can be made 4 hours ahead. Cover and chill marinade and kebabs separately. Boil marinade in saucepan until reduced to generous 1 1/4 cups, about 6 minutes. Whisk in butter, apricot preserves, remaining 1 tablespoon brown sugar, 1/2 teaspoon curry powder, and 2 tablespoons whipping cream. Continue boiling sauce until thickened to sauce consistency, about 2 minutes. Season sauce to taste with salt and pepper. Transfer 1/2 cup sauce to small bowl and reserve for basting kebabs during grilling. Leave remaining sauce in saucepan and set aside for serving. Prepare barbecue (medium-high heat). Brush grill rack with olive oil. Grill kebabs 4 minutes; baste kebabs with reserved 1/2 cup sauce. Continue grilling kebabs until browned and cooked medium-rare, turning occasionally, about 4 minutes longer for lamb and 5 minutes longer for pork. Meanwhile, place saucepan with remaining sauce on 1 side of grill to rewarm. Transfer kebabs to platter. Brush warm sauce over kebabs and serve.