01 - Whisk together flour, cocoa powder, baking powder, and salt in a medium bowl until thoroughly combined. Set aside for later use.
02 - In a large bowl, whisk melted butter and granulated sugar until well blended. Add eggs one at a time, beating thoroughly after each addition. Incorporate vanilla extract, vinegar, and red food coloring until uniform in color.
03 - Gradually add dry ingredients to the wet mixture, alternating with buttermilk. Begin and end with dry ingredients. Mix only until just incorporated—overmixing will toughen the cookies.
04 - Cover bowl and refrigerate dough for minimum 2 hours or until firm enough to handle. This step is essential for proper cookie shape and texture.
05 - Preheat oven to 350°F. Line two baking sheets with parchment paper and set aside.
06 - Place powdered sugar in a shallow bowl. Scoop chilled dough by tablespoonfuls, roll into smooth balls, and generously coat each ball completely in powdered sugar.
07 - Place coated dough balls 2 inches apart on prepared baking sheets to allow for spreading during baking.
08 - Bake for 11 to 13 minutes until cookies are puffed and surface shows characteristic crackling. Centers should remain soft when lightly touched.
09 - Let cookies rest on baking sheets for 5 minutes to set. Transfer to wire rack to cool completely before storing.