In a mixing bowl, combine the sifted flour and powdered sugar. Add the cold, cubed butter and use your fingertips or a pastry cutter to work it into the flour until the mixture resembles coarse crumbs.
Pour in the vanilla extract and gradually add a few tablespoons of cold water, mixing gently until the dough begins to come together. Knead lightly just until smooth, then wrap in plastic wrap and chill in the refrigerator for about 15 minutes.
Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Remove the dough from the fridge and roll it out on a lightly floured surface into a thin rectangle, about 1/8 inch thick.
Spread a generous layer of condensed milk evenly over the rolled-out dough, leaving a small border around the edges. The condensed milk will create a buttery, caramel-like filling when baked.
Starting from one long side, carefully roll the dough tightly into a log, pressing gently to seal the edge. Use a sharp knife to cut the roll into 8 even pieces, about 1 inch thick each.
Place the rolls on the prepared baking sheet, spaced slightly apart. Bake in the preheated oven for about 20-25 minutes, or until the edges are golden brown and the rolls look puffed and flaky.
Remove the baking sheet from the oven and let the rolls cool slightly. They should be tender inside with a crisp outer crust and a glossy caramel aroma.
Serve the warm rolls for a soft, flaky, caramel-scented treat. Enjoy the contrast of their tender interior and crispy outer layer.
