Combine chocolate powder and corn oil.
mix it well and leave aside.
Separate the egg yolk with the egg white.
In a mixer, combine egg white and cream of tartar. Gradually add in 50g
of the sugar. Beat the egg white until it is stiff.
In another mixing bowl, combine egg yolks
and the rest of 40g of sugar. beat the egg yolks until it is fluffy.
Add in milk and corn oil. Gradually sift the flour into the mixture.
Preheat the oven to 340°F. Pour 1/3 of
the egg white mixture into the mixture in step 3. Stir it gently to
combine both. Pour the mixture back into the egg white mixture and stir
gently to combine.
Pour the mixture into baking pan. Bake
for 40 minutes. Remove from oven and inverse the cake. Leave it to
cool.