In the bowl of a stand mixer fitted with the paddle attachment combine flour, salt, cubed butter, powdered sugar, nuts, and vanilla seeds. Mix at medium speed until a crumbly dough forms, about 1-2 minutes. If the dough is too crumbly add 1-2 Tbsp milk.
Use your hands to press the dough together and wrap it in plastic wrap. Chill the dough for one hour in the fridge.
Preheat the oven to 350°F (177°C) and line one or two baking sheets with parchment paper.
Roll the chilled dough into a log approximately ½ inch thick. Cut the log into 1 ½-inch pieces, form the pieces into small cylinders and taper the ends into dull points. Bend each one into a crescent shape. Place the Vanillekipferl on the baking sheet about 1 inch apart.
Bake the Vanillekipferl one cookie sheet at a time for 12 to 15 min (depending on the size of the cookies) until the edges are golden. They should not brown.
Scrape out vanilla pod and combine with powered sugar. This works great in a small food processor. Sift the mixture over the hot Vanillekipferl. Let them cool completely then give them a second dusting.
These cookies keep fresh for about 3 weeks in an airtight container stored in a cool place.
