Method
1. Sift all purpose flour, cocoa powder and baking soda into a clean medium bowl
2. Add unsalted butter to a clean large mixing bowl
3. Beat until smooth
4. Add light brown sugar, white sugar, vanilla extract and sea salt to the large mixing bowl
5. Beat until fluffy - approx 2 min
6. Transfer content of medium bowl to large mixing bowl
7. Beat until just blended
8. Add bittersweet chocolate to the large mixing bowl
9. Mix in evenly
10. Divide into halves
11. Roll into logs
12. Wrap with plastic wrap
13. Chill in fridge until firm - approx 3 hr
14. Pre-heat oven - 160°C
15. Line 2 clean baking sheets with parchment paper
16. Cut into rounds
17. Place evenly
18. Sprinkle with sea salt
19. Bake until dry - 12 min
20. Transfer onto cooling rack
21. Cool
22. Serve