Foolproof sponge cake

Directions

1. 1
   Preheat oven at 345F.
2. 2
   Use parchment paper to line the bottom of the pan, do NOT spray the side of the pan.
3. 3
   Mix all-purpose flour and corn starch well.
4. 4
   Mix vegetable oil, milk and vanilla extract
5. 5
   Separate egg yolks and egg white.
6. 6
   In a dry and clean mixing bowl, beat egg white until foamy, then add cream of tartar and salt.
7. 7
   When the mixture looks like shaving cream, slowly add sugar.
8. 8
   Beat until almost stiff peak.
9. 9
   On the lowest mixing setting, add the egg yolks one by one, then slowly add the oil and milk mixture.
10. 10
    Separate the flour in 3 parts, on the slowest mix setting, add one part of flour at a time.
11. 11
    Do NOT try to over mix otherwise the batter will lose its volume.
12. 12
    At the end, use a spatula to fold the batter to make sure there is no lumps.
13. 13
    Pour in the batter into the pan.
14. 14
    Lift the pan up about half a foot and drop it on the counter in order to break the big bubbles.
15. 15
    Bake at 345F for 25-35 minutes.
16. 16
    Use a toothpick to check.