Sieve the all purpose flour, powdered sugar and baking soda in a bowl. Mix well and keep aside.
Make a well in the centre of the bowl and pour milk, melted butter and vanilla essence. Fold gently using spatula.(Do not add milk in one go, add as required to form smooth batter).
Add vinegar and mix well to form a smooth batter.
Grease microwave safe bowl and pour the batter in and bake for 3 minutes.
Once done, let the vanilla cake stand at room temperature for 5-6 minutes.
Slowly release the sides with knife and demould it.
Your cake is ready to serve!!
