Rea's Sponge Cake

I think I have a privilege to call this "Rea's Sponge Cake" since I've made a lot of trial by my own until I found the perfect sponge cake recipe like I want. Spongy, cotton soft, light textured and slightly fall when it cooled.

A recipe from Rea's Cake

Ingredients:
6 eggs (around @60 gr)
150 gr caster sugar
140 gr plain flour, sifted
1 ½ tbsp water
1 ½ tsp vanilli essence/ 1 tsp vanilli extract/1 small vanilla pod.
75 ml vegetable oil

How to:
Pre-heat the oven. Lightly greased Ø22 cm round cake tin with shortening and lined with baking parchment.
Combine eggs, sugar, water and vanilla in a big bowl and whisk with electric mixer until very pale and fluffy. The other parameter is double-sized mixture and leaving tracks.
Add flour. Whisk in a very low speed.
Stir in oil. Gently combine. (be careful for not over-mixing in this step)
Pour into the prepared tin. Tap tin several times on table to loose air bubbles.
Bake for 40 minutes or until inserted skewer comes out clean.
When it’s cooked, allow the cake to cool in the tin for 10 minutes before turning it out. Remove & cool it completely.