Heat a medium cast iron skillet over medium heat. Add the pepper and blister the pepper on all sides, about 6 minutes. Remove from the pan and add to a small re-sealable plastic bag and close it for about 15 minutes.
This will let the pepper to continue to steam and the skin will be easier to remove. Once cool, remove the skin of the peppers then slice the peppers open and discard about the top ½ inch of the pepper and discard the seeds. Dice the peppers and set aside.
Heat a large skillet over medium heat, add 1 tablespoon of the butter and allow it to melt. Add one of the tortillas and evenly spread pulled pork, cheeses and diced peppers on top.
Add the other tortilla on top and cook until the bottom quesadilla is golden brown, about 1 to 2 minutes. Flip the quesadilla and continue to cook until the cheese is melted and the other side is golden brown, about an additional minute and a half.
For the creamy chipotle BBQ sauce:
In a small bowl whisk together the sour cream, BBQ and chipotle powder until completely combined. Refrigerate until ready to use.
For serving:
Serve the quesadillas cut into 6 equal pieces. Drizzle with the chipotle BBQ sauce or serve on the side.