Lemon Polenta Pistachio Buttons

Lemon Polenta Pistachio Buttons 
8 tablespoons (1 stick) unsalted butter 
1/4 cup sugar 
1 tablespoon lemon zest (about 1 lemon) 
2 teaspoons vanilla extract 
1 large egg 
1 cup all-purpose flour 
1/4 cup fine cornmeal 
1 teaspoon baking powder 
1/2 teaspoon kosher salt 

Sugar Dipping Mix 
2 tablespoons sugar 
1/4 cup finely chopped, roasted, and salted pistachios 
1 tablespoon lemon zest (from about 1 lemon) 

Preheat the oven to 350 degrees F, and place rack in center of the oven. Line a baking sheet with parchment paper. 

In a small saucepan, melt butter and remove from heat. Pour butter into a medium bowl and add sugar, lemon zest, vanilla, and egg. Stir together with a wooden spoon or rubber spatula. In a separate small bowl combine flour, cornmeal, baking powder, and salt and still to combine. Add butter/egg mixture to dry and mix until well combined. Refrigerate batter until firm, about an hour or up to overnight. If refrigerating overnight store in an airtight container. In a small bowl combine sugar, pistachios, and lemon zest to make sugar dipping mix. Roll cookie dough into rounded 2 tablespoon-sized balls and roll around in sugar mix pressing firmly to allow sugar mix to adhere to cookies. (You’ll likely end up with a little dipping mix leftover.) 

Place on prepared baking sheet. Press cookies flat with the palm of your hand; these don’t spread very much on their own. Bake for about 15 to 18 minutes until golden brown on edges and pale in center and baked through. Cool on cooling rack. Store cookies in an airtight container for up to 2 days. The cookie batter may be stored in the fridge for up to a week or the freezer for three weeks and the sugar dipping mix can be stored in an airtight container for up to a week at room temperature.