In a large mixing bowl, combine chilled all-purpose flour, cold butter, granulated sugar, and salt. Use a pastry cutter or your fingers to mix until it resembles coarse meal. Add an egg and whole milk to bind the mixture. Stir until just combined, ensuring not to overwork the dough. Shape into a ball, wrap in plastic, and refrigerate for at least 2 hours.

After chilling for a couple of hours, remove the dough from the refrigerator and let it sit at room temperature for about 10 minutes. This will make it easier to roll out. Meanwhile, preheat your oven to 375°F (190°C), preparing a baking sheet lined with parchment paper for the Wisconsin Apple Kringle.

While the dough chills, peel, core, and slice your apple varieties into thin pieces. In a medium bowl, mix the apples with brown sugar, ground cinnamon, nutmeg, and lemon juice. Stir until the apples are well coated and let the filling sit to allow the flavors to meld.

On a floured surface, roll out the chilled dough into a large rectangle about 1/4 inch thick. Carefully transfer it to the prepared baking sheet. Spoon the apple filling along the center of the dough, leaving space on the edges. Gently fold the dough over the filling to create a loose oval or horseshoe shape, pinching the edges to seal.

Place the shaped Wisconsin Apple Kringle into the preheated oven and bake for 25-30 minutes or until the top is golden brown and the filling is bubbling slightly. Keep an eye on it during the last few minutes, as you want a rich, golden crust. Once done, remove it from the oven and let it cool slightly.

In a small bowl, whisk together powdered sugar, vanilla extract, and a splash of milk until smooth. Drizzle the glaze over the warm Wisconsin Apple Kringle, allowing it to drape beautifully across the surface. Let the glaze set for a few moments before slicing into this flaky delight and serving.