Preheat the oven to 180°C.
In a large mixer bowl, add in plain flour, baking soda, baking powder and salt. Give it a mix and set aside.
In another mixer bowl, cream the butter and sugar until light and fluffy.
Add in the eggs by beating 1 egg at a time.
Sift in half of the flour mixture, then mix the ingredients until combined.
Add in half amount of milk. Mix well.
Add in the remaining flour mixture and milk. Use a spatula to fold the ingredients until combined.
Add in vanilla extract and gently fold to combine all ingredients.
Transfer the batter into a measuring cup then pour into cupcake moulds. Alternatively, you can use a spoon to scoop the batter into cupcake moulds. Fill the cupcake moulds until 70-80% full to allow space for the batter to rise in the oven.
Use a spoon to smooth the top of the cupcake batter.
Bake in the oven at 180°C for 20-25 minutes.