In a medium bowl, add flour. Using a pastry blender or 2 knives, cut bacon drippings and butter into flour until lard is in pea-size pieces. Stir in chives. Refrigerate for 20 minutes.
Preheat oven to 475°. Line a jelly roll pan with parchment paper.
Make a well in center of mixture. Add buttermilk, stirring until dough is moist. Turn dough out onto a lightly floured surface. Lightly sprinkle flour over top of dough. Fold dough 3 to 4 times. Pat dough on a lightly floured surface to ¾-inch thickness. Using a 2½-inch biscuit cutter dipped in flour, cut dough, reshaping scraps and flouring as needed.
Place dough rounds on prepared pan. Refrigerate for 15 minutes.
In a small bowl, whisk together egg, 1 teaspoon water, and salt until frothy. Brush tops of biscuits with egg mixture. Bake until golden brown, about 15 minutes. Serve warm.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/50-50-biscuits/