01 -
Melt margarine in a saucepan over medium heat. Add blueberries, water, sugar, cornstarch, lemon juice, cinnamon, and salt. Cook mixture until bubbling and thickened, approximately 1 minute. Remove from heat and let cool to prevent soggy cookies.
02 -
On a lightly floured surface, roll prepared pie crust to 3-6 mm thickness. Use a 6.5-7.5 cm round cookie cutter to cut circles.
03 -
Place half of the dough circles on a baking sheet. Moisten edges with water. Spoon 1.5 teaspoons of cooled blueberry filling onto each circle. Cover with remaining dough circles and seal edges by pressing and crimping with a fork.
04 -
Whisk egg with 15 ml water to create an egg wash. Brush over tops of cookies for golden color. Optionally, sprinkle sanding sugar and cut slits on top to release steam.
05 -
Preheat oven to 175°C. Bake cookies for 15-20 minutes until golden brown. Transfer to wire rack and cool before serving.