Cut one sheet of thawed all-butter puff pastry into 9 even squares.
Add diagonal slits to the corners of each square, taking care not to cut the centre of the square.
Put each square of puff pastry onto a parchment paper lined baking sheet. Add about 1 tablespoon of the mincemeat to the center of each square. And fold in one corner of each triangle into the center to the center to form the pinwheel. Press the centre down quite firmly.
Bake at 350F for about 10-15 minutes until the pastry begins to turn golden brown. Remove from the oven and cool on a wire rack.
Once cool, sprinkle with powdered sugar and enjoy.