Preheat oven to 350 F. Line cookie sheets with parchment paper.
Whisk together flour, baking powder, baking soda, and salt. Set aside.
Cream shortening and both sugars on medium speed in electric mixer until light and fluffy, about 3 minutes. Add eggs, one at a time, mixing for one minute after each addition. Add vanilla. Reduce mixer to low speed and slowly add flour mixture in 3 additions, alternating with buttermilk in two additions (flour, buttermilk, flour, buttermilk, flour). Turn off mixer and fold in chocolate.
use a cookie scoop and place on cookie sheet, about 1 1/2? apart. Bake for 10-12 minutes, or until edges are lightly browned.
Immediately slide parchment onto cooling rack and let cookies cool for 5 minutes. Transfer cookies from parchment directly to cooling rack to cool completely.