Here is a recipe from Reese Witherspoon, who is quite the cook and baker. The key to this recipe is the frozen, grated butter:
The World’s Best Buttermilk Biscuits
1/2 cup butter (one stick) frozen
2-1/2 cups self rising flour
1 cup chilled buttermilk**
2 tablespoons butter, melted
Preheat oven to 475 degrees F. Grate frozen butter using larger holes of a box grater. Toss together grated butter and flour in a medium bowl. Chill 10 minutes. Make a well in center of mixture, add the buttermilk and stir 15 times. Dough will be sticky. Turn dough out onto a lightly floured surface and lightly sprinkle flour over top o dough. Using a floured rolling pin, roll dough into a 3/4 inch thick rectangle, about 9 x 5 inches. Fold dough in half so short ends meet, repeat rolling and folding process 4 more times. Roll dough to 1/2 inch thickness. Cut with a 2-1/2 inch cutter floured, reshaping scraps and flouring as needed. Place dough rounds on a parchment paper-lined jelly roll pan, bake at 475 degrees F for 15 minutes or until lightly browned. Brush with melted butter and serve hot!
**NOTE: I keep powdered buttermilk powder in the refrigerator at all times. It’s not quite as good as fresh buttermilk, but in a pinch (or at night when I don’t feel like going out to the store), it works quite well.