Method
1. Add all purpose flour and baking soda to a clean medium bowl
2. Whisk briefly until combined
3. Add unsalted butter, granulated sugar, brown sugar, salt, peanut butter, egg and vanilla extract to a clean large mixing bowl
4. Mix until combined
5. Transfer dry ingredients to large mixing bowl
6. Mix until just combined
7. Divide into halves
8. Wrap with plastic wrap
9. Chill in fridge - 2 hr
10. Pre-heat oven - 160°C
11. Line 2 clean baking sheets with parchment paper
12. Form into balls
13. Place content of large mixing bowl on 2 baking sheets
14. Flatten
15. Bake until golden brown - 13 min, 160°C
16. Transfer onto cooling rack