Traditional Homemade Egg Sponge Cake

Ingredients
9 eggs (egg yolks and whites separated)
100g top flour, sifted
100g castor sugar
90ml milk
80ml oil
pinch of salt
¼ tsp cream of tartar (optional)

Instructions

1. Combine the egg yolks, milk and oil in a mixing bowl and beat with a manual balloon whisk till they turn light yellow in colour.
2. Add the sifted top flour and salt and mix well with the balloon whisk till the flour is no longer visible. Set aside.
3. Add the egg whites and cream of tartar (if using) to a mixer with the sugar added progressively and beat till glossy and stiff peaks forms.
4. Add the egg whites batter to the egg yolks batter in 3 or 4 additions and mix well each time using the balloon whisk till the egg whites are no longer visible. The final batter should be smooth flowing and glossy.
5. Pour the batter to a lined 9-inch square baking pan. Knock the pan lightly over the table top to smoothen out the surface.
6. Bake in a pre-heated oven at 160 degrees C for 45 minutes in the middle rack. Once baked, remove from oven and place it on a cooling rack. You can almost immediately invert the cake, remove the parchment paper lining and serve.

Notes

The egg whites should be clear and free from any egg yolks in order for it to beat well. If there happens to be some egg yolks traces in the whites whilst separating them, try removing the egg yolks with a small clean spoon and add the cream of tartar to allow it to beat well.