Beat flour, sugar, buttermilk, eggs, vanilla, salt, and baking powder together in a bowl until dough is thoroughly mixed. Cover bowl with plastic wrap and refrigerate for at least 1 hour.
Preheat oven to 375 degrees F (190 degrees C). Grease baking sheets.
Drop about 2 teaspoons of dough per cookie about 2 inches apart onto prepared baking sheets.
Bake cookies in the preheated oven until light golden brown, about 10 minutes. Cool cookies for 8 to 10 minutes before removing to a plate to decorate.
Press candy corns, point-end first, partway into the top edge of the cookies to resemble feathers. Place 2 candy-coated milk chocolate pieces in the center of each cookie to resemble the turkey's eyes. Use a small amount of frosting to create the turkey's mouth. Press 2 pieces of licorice into the bottom edge of the cookie to make the turkey's legs.