Toast the pecans lightly in a dry sauté pan over medium heat, stirring often. Once cool, pulse one cup of the pecans in a food processor until it starts to form a paste. Chop the remaining ½ cup pecans and set aside.
In a small bowl, whisk together the flour, salt and cinnamon and set aside. In a large bowl, use an electric mixer to combine the pecan paste, butter and powdered sugar until well mixed. Mix in the vanilla. Add the flour mixture and mix on low until just combined. Transfer to a bowl, cover with plastic wrap and chill for one hour.
Preheat the oven to 3500 F and line baking sheets with parchment paper. Fill a shallow dish with the remaining 1 ½ cups sifted powdered sugar. Set aside.
Roll a one tablespoon sized ball of cookie dough into a log and then bend to make a crescent shape. Place on cookie sheet and repeat, leaving an inch of space between each cookie. Bake for 15-18 minutes until golden brown.
Let cool on baking sheet for 2-3 minutes. Carefully roll each cookie in the powdered sugar, spooning some over the tops and bottoms.
Once cool, melt the white chocolate in a double boiler over the stove, stirring occasionally. Transfer the white chocolate to a baggie or pastry bag fitted with a small round tip. Drizzle the chocolate over the cookies and sprinkle some of the remaining chopped pecans over the top. Freeze to set up the chocolate completely. Can be served chilled or room temperature.