Preheat oven to 425°F. On a foil-lined baking sheet, arrange chips with some chips overlapping.
Heat pulled pork according to package directions in microwave. Cool slightly, then scatter pork onto chips. Sprinkle with cheese, and bake 5 minutes or until cheese is melted and chips are thoroughly heated.
Thin sour cream with 2 - 3 tablespoons of water; drizzle over nachos. Sprinkle with green onions, and drizzle with barbecue sauce, if desired.