Heat a 10-inch nonstick saute pan over medium-high heat. Place 1 tortilla in the dry pan for approximately 1 minute per side, or until it just begins to brown. Remove. Repeat with the second tortilla. (If your tortilla expands like a blowfish, poke it with a fork to release the hot air.)
After the second tortilla has browned, leave it in the pan and reduce heat to medium-low. Spread half of the mango evenly over the tortilla, then top with half of the peppers, scallions, cilantro, and Brie strips. Top with the first tortilla. Cover the pan with a lid, reduce heat to medium-low, and cook for 2 minutes.
Flip the quesadilla with a spatula, re-cover the pan, and continue cooking for 2 more minutes. (Don't worry if a bit of cheese escapes and begins to sizzle loudly.)
Remove the quesadilla from the pan, let sit for 1 minute, then slice into 8 wedges (like a pizza). Serve immediately with the sour cream dipping sauce.
Repeat with the remaining ingredients. Serve with Sour Cream and Lime Dipping Sauce.
Sour Cream and Lime Dipping Sauce:
Blend sour cream, lime juice and salt with a fork until the mixture is smooth. Transfer to a small decorative bowl or teacup and refrigerate.