In a medium saucepan combine all of the sauce ingredients and stir to combine. Bring to a simmer. Reduce heat to low and simmer for 30 minutes. Remove from the heat.
Heat the oven to 450 degrees F. Line a 18×13 inch baking sheet with aluminum foil. Spread the sliced romaine lettuce across the bottom of the pan. Top with half of the mozarella cheese and sprinkle wih half of the red onion.
Place the corn chips on top of lettuce and spread the chips out evenly.
In a small saucepan, add the cream and bring to a boil over medium heat. Add the cheese slices, one or two at a time, only adding after the first pieces have melted. Do this while stirring constantly to combine the cheese with the cream. Once the cheese has melted turn the heat down to a simmer.
Mix the pulled pork with a couple of tablespoons of the bbq sauce. Spread the pork out on top of the chips. Sprinkle with the remianing mozerella. Place into the oven and bake for 10 minutes or until the chips begin to brown. Remove from the oven.
With a spoon drizzle the bbq sauce across the chips to taste. Spoon the cheese sauce across the top and then top with green onion and remaining red onion.