If using Pepperidge Farm puff pastry, on a lightly floured work surface, roll out each sheet of puff pastry, 1 at a time, to an 11-inch square and cut into 4 squares for a total of 8 squares. Turn a pastry square so one corner is toward you and crumble 1/8 of the almond paste (about 1 tablespoon) over the bottom half of the square, leaving a 1/4 inch border along both edges. Top with 1/8 of the mixed berries and fold the top half of the pastry square over the filling to form a triangle. Gently but firmly press the edges together, crimp with a fork to seal, and transfer to the prepared baking sheet. Repeat with the remaining puff pastry and filling. If using Dufour puff pastry, on a lightly floured work surface, roll out the sheet puff pastry just a little to smooth any crease marks and cut it into 6 squares. Turn a pastry square so one corner is toward you and crumble 1/6 of the almond paste over the bottom half of the square, leaving a 1/4 inch border along both edges. Top with 1/6 of the mixed berries and fold the top half of the pastry square over the filling to form a triangle. Gently but firmly press the edges together, crimp with a fork to seal, and transfer to the prepared baking sheet. Repeat with the remaining puff pastry and filling.