In a medium pan, melt the butter. Add the brown sugar, cinnamon, ginger, and salt, and stir until the sugar has melted completely and formed a sauce. Add the apples and toss until the apples are fully coated in the sauce. Remove pan from heat.
3. Step
On a floured surface, roll out the puff pastry until it has doubled in size. Cut 4-inch squares.
4. Step
Whisk egg with 1 tablespoon of water to form an egg wash.
5. Step
Fill each square with 1½ tablespoons of apples. (Reserve extra syrup from apples.) Brush the edges of the squares with egg wash. Fold each corner of pastry over the apples until the apples are completely enclosed in the dumpling. Brush entire dumpling with egg wash.
6. Step
Bake for 18–20 minutes, until golden brown. Dust with powdered sugar and drizzle with reserved syrup.
