1. Cook bacon in a large skillet over medium-high heat 8 to 10 minutes or until crisp; remove bacon, and drain on paper towels, reserving 2 Tbsp. drippings. Crumble bacon; set aside.
2. Stir together reserved bacon drippings, potatoes, next 5 ingredients, and 2 cups Cheddar cheese in a large microwave-safe bowl. Microwave at HIGH 4 minutes. Stir in sour cream and chiles until well blended.
3. Spoon potato mixture into a lightly greased 13- x 9-inch baking dish. Sprinkle evenly with bacon and remaining 1 cup Cheddar cheese. Arrange pork evenly over cheese. Drizzle barbecue sauce evenly over pork.
4. Bake at 350° for 45 minutes. Let stand 10 minutes before serving. Garnish, if desired.