In a mixing bowl, whisk together 2 cups of all-purpose flour and 1 teaspoon of salt until evenly combined.

Cut in 1 cup of cold unsalted butter using a pastry cutter or your fingers until the mixture resembles coarse crumbs.

Gradually add 1/4 cup of ice water, mixing until a dough forms.

Shape the dough into a rectangle, wrap it in plastic wrap, and chill in the refrigerator for at least 2 hours.

Preheat your oven to 350°F and toast 1 cup of blanched slivered almonds on a baking sheet for about 10 minutes.

Remove from the oven and let cool, then grind the almonds in a food processor until fine.

In a saucepan, combine the ground almonds, 1/2 cup of granulated sugar, 1/4 cup of heavy cream, 1 tablespoon of all-purpose flour, 1 teaspoon of almond extract, and a pinch of salt.

Cook over medium heat for 5-7 minutes until thickened, then let it cool completely.

Preheat the oven to 375°F and line a baking sheet with parchment paper.

Roll out the chilled dough on a floured surface into two rectangles, each measuring 12x18 inches.

Spread half of the cooled almond filling over one rectangle, then fold the other rectangle over the top.

Transfer the kringle to the prepared baking sheet and bake for 25-35 minutes.

Once baked, remove the kringle from the oven and allow it to cool on a wire rack for about 10 minutes.

Whisk together 1 cup of sifted powdered sugar and 2-4 tablespoons of milk or heavy cream until smooth.

Drizzle the glaze generously over the top and garnish with additional slivered almonds.