1. Preheat the oven to 400 F and line 2 baking trays with parchment paper.
2. In a large bowl, sift the flour, sugar, baking powder, baking soda and salt.
3. In a separate bowl, whisk the buttermilk, egg and oil together. Add this to the flour mixture and stir just until blended.
4. Use an ice cream scoop or 2 tablespoons to drop batter (about ¼ cup each) onto the prepared baking trays, leaving 2-inches between them. Bake the biscuits for about 15 minutes until they are a light golden brown and lift away from the parchment easily.
5. Serve the biscuits warm from the oven, or re-heated at 300 for 10 minutes. The biscuits are best enjoyed the day they are baked.