In a mixing bowl, combine flour, baking powder, and salt. Cut in the cold butter until the mixture resembles coarse crumbs. Stir in cold water until a dough forms.

Wrap the dough in plastic wrap and refrigerate for at least 30 minutes.

In a bowl, mix the sliced peaches with sugar, cinnamon, and lemon juice. Set aside.

Preheat the oven to 375?F (190?C). Roll out the dough on a floured surface to about 1/8 inch thick.

Cut the dough into squares. Place a spoonful of the peach filling in the center of each square. Fold the dough over to form a triangle and seal the edges.

Place the dumplings in a greased baking dish. In a saucepan, combine water, sugar, and vanilla extract to make the syrup. Bring to a boil, then pour over the dumplings.

Bake for 25-30 minutes or until golden brown. Serve warm with syrup.