A little unconventional shape, but it is very delicious, a Chiffon cake.
It is very famous in Japan, China, and some places in the US, and there are variants including macha (green tea) Chiffon, etc.
First beat thoroughly:
6 egg yolks
50 g sugar
then add 70 g of oil (tasteless vegetable oil like refine rapeseed oil or sunflower oil)
90 g of milk (1.5 or 3.5% fat)
mix it by hand (whisk).
add 120 g of flour (self rising) or ordinary flower (add 1 flat tablespoon of baking powder and mix dry before adding) and mix with whisk (only as long as needed).
6 egg whites
slowly add in about 5 portions: 60 g sugar
Add the egg whites to the flour mixture, first add 1/3, then mix slowly, then add the rest, mix just enough so that the dough is homogenous.
Fill to non-greased suitable baking mould.
Bake at 170°C for 35 min.
Let cool down for 3 hours upside-down.
Better to cover the bottom of the mould with non-stick paper.