Separate the egg yolk for white in a separate bowl.
Beat well the egg yolk until softened.
Then add the oil, vanilla, 1 cup of sugar, salt, royal, corn starch, baking powder, and flour. Mix well and set aside.
Use an electric mixer to beat the egg white, while mixing the sugar slowly onto the egg white for 10 minutes or until fluffy.
Then, pour the egg yolk mixture onto the egg white mixture and mix it using a spatula. Mix well.
Preheat oven to 160 degrees C.
Fill the round baking dish with the mixture and bake it for 55 minutes.Tip: Don't open the oven for 55 minutes. After 55 minutes, remove the cake from the oven. Let it cool for 10 minutes.
After 10 minutes, make slices. Serve and enjoy!