Preheat oven to 350oF (180oC).
Grease sides and bottom of round cake pan (7x3 inch, 18x7 cm). Line bottom of pan with parchment paper.
In a bowl, sift flour, baking powder, baking soda and salt.
To the same bowl, add sugar and mix.
Add vegetable oil, water, vinegar (or lemon juice) and vanilla extract. Mix until dry flour no longer visible. Do not over mix.
Transfer batter to prepared cake pan (7x3 inch, 18x7 cm).
Bake in preheated oven 350oF (180oC), 50-55 minutes or until toothpick comes out clean.
Let cake cool down in pan for 10 minutes. Then transfer to wire rack and let it cool down completely.
Top with vegan coconut oil frosting.