📋 Instructions

1. 1Make the Dough — Whisk the flour and salt, then cut in the cold butter with a pastry cutter until pea-sized lumps remain. Drizzle in the ice water one tablespoon at a time and squeeze a handful; if it holds together, you're done.
2. 2Chill the Pastry — Flatten the dough into two discs, wrap them, and refrigerate for 30 minutes until firm but still pliable. Cold dough rolls without sticking and bakes up flakier.
3. 3Cook the Filling — Simmer the apples, brown sugar, cinnamon, and cornstarch in a small saucepan over medium heat for 6 to 8 minutes, until the apples soften and the juices bubble and thicken. You'll hear a slow, sticky plop rather than a watery simmer; scrape it onto a plate to cool completely.
4. 4Roll and Cut — Roll each disc to 1/8 inch (3mm) on a floured surface and cut into 3x4-inch rectangles, re-rolling scraps once. You should get 12 rectangles total.
5. 5Fill and Seal — Spoon 1 heaping tablespoon of cooled filling onto 6 rectangles, leaving a 1/2-inch border. Top with the remaining rectangles, press the edges closed, and crimp with a fork; brush with egg wash and prick the tops twice.
6. 6Chill the Tarts — Freeze the assembled tarts on a lined tray for 10 minutes while the oven heats. This firming step is what keeps the seams sealed.
7. 7Bake Until Golden — Bake at 375°F (190°C) for 22 to 25 minutes, until deep golden brown at the edges and the filling bubbles at the vents. The pastry should sound hollow when tapped and read 200°F (93°C) at the center.
8. 8Glaze and Set — Whisk the powdered sugar, milk, and vanilla until smooth, then spread over the tarts once they've cooled for 10 minutes. Let the glaze set for 15 minutes before serving; it should look glossy, not runny.