Preheat oven to 350 degrees and line two baking sheets with parchment paper.
Cut each sheet of puff pastry into 8 equal squares. Cut diagonally on each corner to just about the middle, but still allowing them to be attached. Fold over each corner to and press into the middle. Remember you are working with puff pastry, so even if it does not look at all nice and pretty now, it will after it bakes and puffs.
Bake for 15 minutes or until very lightly browned. As soon as you remove from the oven, dot the centers with a small square of brie and then a blackberry. It is important to do this while pinwheels are warm so the brie melts enough to stick to the pastry and the blackberry to the brie.
Finish by sprinkling turbinado or powdered sugar over top. Serve while warm or at room temperature.
If you've tried this recipe, come back and let me know how it was!