How to Make It
Preheat the oven to 400°. Line a baking sheet with parchment paper.
Unfold the pastry on a lightly floured work surface. Cut the pastry into 12 equal rectangles and arrange on the lined baking sheet. Bake until golden brown, 12 to 15 minutes. Transfer to a wire rack to cool for 10 minutes.
Split each pastry into 2 layers. Spread 1 teaspoon pineapple preserves on each of the bottom layers. Spread 1 teaspoon dulce de leche on each of the top layers. Reassemble the pastries (like sandwiches), sprinkle with confectioners’ sugar and serve.