Preheat oven to 350oF (180oC).
Grease sides and bottom of round cake pan (7 inch, 18 cm diameter). Line bottom of pan with parchment paper. Set aside.
To a bowl, add sugar, vanilla extract, lemon juice / white vinegar and water. Whisk until sugar is completely dissolved.
Then add oil and mix well.
Sift in flour, baking powder and baking soda.
Mix until dry flour is no longer visible. DO NOT OVER MIX (mix until dry and wet ingredients are just combined).
Transfer batter to prepared cake pan. Spread batter evenly.
Bake in preheated oven at 350oF (180oC) for 35 minutes. or until toothpick inserted in the middle of cupcake comes out clean.
Let cake cool down for 5-10 minutes in pan. Then, transfer to wire rack to cool down completely.
