Preheat oven at 345°F. Use parchment paper to line the bottom of the pan, do NOT spray the side of the pan.

Mix all-purpose flour and corn starch well.

Mix vegetable oil, milk and vanilla extract

Separate egg yolks and egg white.

In a dry and clean mixing bowl, beat egg white until foamy, then add cream of tartar and salt. When the mixture looks like shaving cream, slowly add sugar. Beat until almost stiff peak.

On the lowest mixing setting, add the egg yolks one by one, then slowly add the oil and milk mixture.

Separate the flour in 3 parts, on the slowest mix setting, add one part of flour at a time. Do NOT try to over mix otherwise the batter will lose its volume. At the end, use a spatula to fold the batter to make sure there is no lumps.

Pour in the batter into the pan. Lift the pan up about half a foot and drop it on the counter in order to break the big bubbles.

Bake at 345°F for 25-35 minutes. Use a toothpick to check.