Preheat oven to 450°. In a large bowl, mix hash browns, Parmesan cheese, egg whites and seasonings until blended. Divide potato mixture among 18 well-greased muffin cups; press on the bottoms and up the sides to form cups., Bake until edges are dark golden brown, 22-25 minutes. Carefully run a knife around sides of each cup. Cool 5 minutes before removing from pans to a serving platter. Meanwhile, heat pulled pork according to package directions., Sprinkle cheese into cups. Top with pork, sour cream and bacon; sprinkle with chives. Serve warm.