Beat yolks, one and a half cups sugar, and oil.

Add baking powder, water, liquor, vanilla sugar, and three cups of flour.

Beat egg whites until stiff, add two cups of sugar and beat until peaks form.

Fold beaten egg whites into yolk mixture. Add remaining cup of flour by hand.

Pour into 10- by 16-inch pan.

Bake for one hour.

Preheat the oven to 350 degrees Fahrenheit.