Separate the egg whites and yolks.
In a bowl, mix the egg yolks with the sweetener.
Add cooking oil and milk, and mix well.
Gradually add sweetener to the egg whites to make meringue.
Combine the yolk mixture with the meringue.
Add sifted cake flour and mix.
Pour the batter into a pan lined with parchment paper.
Bake in a preheated oven at 170°C for 30 minutes.
After cooling, whip the fresh cream and fill the center.