In a large mixing bowl, whisk together all-purpose flour, granulated sugar, and salt. Cut in cold butter until the mixture resembles coarse crumbs. In a small bowl, combine warm milk and active dry yeast; let it sit for 5 minutes until foamy. Add this mixture along with a large egg to the flour mixture, stirring until a dough forms. Cover the bowl with plastic wrap and chill in the refrigerator for 1 hour.

Once your dough has chilled, lightly flour your work surface and roll the dough into a rectangle about 15 inches long and 10 inches wide. Spread the apple pie filling down the center of the dough, leaving about 2 inches on either side. Fold the sides of the dough over the filling, creating a horseshoe shape, and pinch the seams to seal. Place the kringle on a lined baking sheet.

Preheat your oven to 350°F (175°C). Brush the top of the kringle with an egg wash made from a beaten egg and a splash of water. Bake for 25-30 minutes, or until the pastry is golden brown and flaky.

Let it cool on the baking sheet for about 10 minutes. Meanwhile, prepare the glaze by mixing powdered sugar, vanilla extract, and a couple of tablespoons of water or milk until smooth. Drizzle the glaze over the warm kringle.

Once glazed, slice the kringle into generous portions, ready to be served. Enjoy warm or at room temperature.