Preheat oven to 375°F. Line two baking sheets with parchment paper.
In a large bowl, whisk together flour, cocoa powder, baking powder, baking soda, and salt.
In another bowl, whisk together sugar, buttermilk, sour cream, egg, red food coloring, and vanilla.
Slowly add the dry ingredients into the wet ingredients, stirring just until combined.
Fold in the melted butter until the dough comes together. Chill for at least 30 minutes.
Scoop tablespoon-sized portions of dough and roll them into balls.
Roll each dough ball in powdered sugar and place them on the baking sheets, spacing 2 inches apart.
Bake for 10-12 minutes or until the cookies are crinkled and set at the edges.
Cool on baking sheets for 5 minutes, then transfer to a wire rack to cool completely.