Line a baking sheet with parchment paper and preheat the oven to 400 F.
Brush the outsides of each tortilla with melted butter and place a layer of apples and cheese and a sprinkle of walnuts in each. Fold in half (I used the brie to hold it shut ad the cheese seemed to make it stick well together. Sprinkle with brown sugar and bake for 8 to 10 minutes until tortillas are beginning to turn golden and cheese is melting.
Let cook for a few minutes before serving and drizzle with caramel sauce.