Soviet Oreshki "Walnut" Cookies (Орешки)

Add flour, powdered sugar, granulated sugar, and salt to your mixer’s bowl and stir (on lowest speed) with pedal attachment for 1 minute. While still stirring on lowest speed, add cold butter 1 tbsp at a time. Continue stirring until the mixture resembles corn meal like texture (about 5 minutes). Add 1 beaten egg and vanilla, while still stirring on lowest speed. Dough will come together very quickly at this point, do not overmix. As soon as the dough started coming off the sides of the bowl, turn off the mixer and transfer all dough onto the plastic wrap. Loosely form a ball, wrap into plastic wrap and refrigerate for 30 minutes.

After the dough has firmed up in refrigerator for 30 minutes, remove it from the plastic wrap. Pinch out aproximately a half teaspoon amount of dough and form small balls.

Preheat the Oreshki/Walnut Cookies pan/form according to instructions. Fill each cavity of the form with the dough balls and cook each side for about 2-3 minutes, following the instructions of the form/pan.

This step can be done way ahead of time, or right before starting making the dough.

Place both cans of sweetened condensed milk into a large pot, fully cover with water (cans must be completely submerged in water), cover the pot and bring to boil on high heat. Once the water is boiling, reduce the heat to low (make sure the water is still slightly boiling), and cook for exactly 2 hours, covered. Once 2 hours have passed, carefully pour out the water from the pot, leaving the cans in, and add cold water leaving the cans to completely cool off. Sealed cans of this homemade dulce-de-leche can stay at room temperature for up to 30 days.

Once all walnut/oreshki baked halfs have cooled, fill with aproximately half a teaspoon of the dulce de leche and adhere together. Refirgerate the filled cookies for at least 30 minutes. Optional: dust with powdered sugar before serving.