Preheat oven to 325°F and set aside a parchment lined baking sheet.
In a large bowl, combine flour, sugar, pistachios, butter, vanilla, and salt. Mix on low speed until the dough comes together and forms a cohesive ball.
Roll the prepared dough out between two sheets of parchment paper (using parchment paper eliminates the need to flour a surface, thus preventing the cookies from absorbing too much flour) to ¼-inch to ½-inch thickness. Cut the dough into 2 to 3-inch circles and place 1-inch apart on the prepared baking sheets. Refrigerate for at least 1 hour to prevent spreading.
Bake until the edges of the cookies start to turn light golden, about 11 to 13 minutes. Cool on the baking pan for 5 minutes, then transfer to a wire rack and cool completely.
Optional: To add a chocolate garnish, simply dip or drizzle melted chocolate on the cookies and place on a parchment lined baking sheet until it's set.