Ingredients :

• Shortcrust pastry — Store-bought dough works very well here—that’s the whole point of the recipe. Choose an all-butter shortcrust for flavor and crispness. Take it out 15 minutes before working with it, otherwise it will crack when you cut it and the edges won’t seal properly.
• Apple filling — Canned or homemade, both work. If using canned, drain the excess juice—a filling that’s too liquid will soak the dough before baking even starts. Dice the pieces small if the canned ones are too large: thick chunks will deform the turnovers when closing and cause the dough to crack.
• Beaten egg — A single egg, whisked with a pinch of salt. It serves to seal the edges hermetically and give that light caramel color to the crust. No yolks alone, no water instead—the whole egg is the right balance between browning and glue.
• Cinnamon sugar — Mix it yourself: 3 parts white sugar to 1 part ground cinnamon. Sprinkle generously but don’t overdo it—you want a slightly grainy surface that crunches, not a sandy crust that masks everything else.