Method
1. Pre-heat oven - 200°C
2. Add buttermilk and egg to a clean medium bowl
3. Whisk together and set aside
4. Add all purpose flour, baking soda, cream of tartar and salt to a clean large mixing bowl
5. Whisk together until blended
6. Add unsalted butter to the dough
7. Rub in and set aside
8. Transfer milk mixture to dough
9. Add cheddar cheese to the dough
10. Mix well
11. Turn out on lightly-floured surface
12. Knead gently until smooth
13. Shape
14. Transfer dough to baking sheet
15. Cut
16. Bake until hollow-sounding when tapped - 30 min, 200°C
17. Let cool