Method
1. Pre-heat oven - 170°C
2. Line a clean muffin pan with paper muffin cups
3. Add unsalted butter and superfine sugar to a clean large mixing bowl
4. Cream until fluffy
5. Add vanilla extract to the batter
6. Add egg to the batter one by one while mixing
7. Add all purpose flour and baking powder to a clean medium bowl
8. Whisk briefly until combined
9. Transfer dry ingredients to the butter-sugar mixture
10. Add lemon juice and zest
11. Mix until well combined
12. Add milk to the batter if it seems dry
13. Transfer batter to muffin pan filling cups 2/3 full
14. Bake until skewer tests clean - 18 min, 170°C
15. Transfer onto cooling rack and leave until completely cool
16. Add salted butter and powdered sugar to a clean large mixing bowl
17. Mix until well combined
18. Add lemon juice and zest and mix until well blended
19. Spread frosting on cupcakes
20. Garnish with blueberries