01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - Unroll puff pastry on lightly floured surface. Cut into 8 equal rectangles.
03 - Combine dulce de leche with 1/2 teaspoon cinnamon in small bowl, mixing until smooth.
04 - Place 1 generous tablespoon dulce de leche mixture in center of each rectangle. Fold pastry to form squares or triangles. Press edges firmly with fork to seal.
05 - Arrange pastries on prepared baking sheet. Brush tops generously with beaten egg.
06 - Mix 2 tablespoons sugar with 1/2 teaspoon cinnamon. Sprinkle evenly over egg-washed pastries.
07 - Bake 18-20 minutes until pastries are puffed and golden brown.
08 - Cool slightly on baking sheet. Serve warm or at room temperature.