1. Combine the flour, baking powder, baking soda, and salt in a large bowl, and mix to combine.
2. Place the butter into the flour mixture, and use a pastry cutter to break up the butter into smaller pieces; the mixture should look crumbly but still have some larger pieces of butter.
3. Toss in the shredded cheese, bacon, and chives; use your hands to toss the ingredients together.
4. Whisk together the buttermilk and the egg.
5. Slowly pour the buttermilk/egg mixture into the flour mixture, stirring just until the dry ingredients are moistened and a dough forms, if the dough is too wet, add more flour if the dough is too dry, add more buttermilk; you can use a spatula or wooden spoon to do this.
6. Turn the dough out onto a floured surface, and add fold the dough over itself a few times to create some layers, adding extra flour if needed.
7. Use your hands to form the dough into a large circle, about 1/2-1 inch thick, or about an 8-inch circle.
8. Use a knife to cut the circle in half one way, then the other, then cut each half in half, this will create 8 slices.
9. Place the scones onto a baking sheet lined with parchment paper, and place in the fridge for about 10 minutes, OR if you want to make these ahead of time, this is the point when you would place them in the freezer.
10. Then, brush the tops with a little bit of buttermilk, using a pastry brush.
11. Bake at 375 degrees for about 15-17 minutes, or until the edges start to become golden, if baking these right from the freezer it may take closer to 20-25 minutes to bake.