Heat the oven to 375°F (190°C) and line a large baking sheet with parchment paper.
Mix the preserves with cornstarch and lemon zest. This slightly thickens the filling and helps prevent excessive leaking.
Roll out the pastry and cut pairs of quirky witch shapes with triangular bodies, pointed hats, and small protruding arms.
Spoon about 1 teaspoon of jam into the center of half the shapes, keeping the filling away from the edges.
Cover with matching pastry pieces. Crimp the perimeter firmly with a fork, then carefully cut crooked eyes and smiling mouths into the upper pastry.
Whisk the egg with water and brush over each pie. Sprinkle lightly with coarse sugar or cinnamon if desired.
Bake for 18–24 minutes until deeply golden and crisp, allowing a little red filling to bubble naturally through the facial openings. Cool for 10 minutes before serving.