How to make
Separate the egg yolks from the whites. Beat the yolks with the sugar, add the oil, then the yoghurt with the baking soda extinguished in it, the vanilla and finally the flour, stirring until you get a homogeneous (smooth) mixture.
Pour the mixture into an oiled tray that you've floured. Bake until ready. Take it out of the oven and pour on the jam, then the whites beaten with 10-11 tbsp sugar.
You can make decorations (rosettes, waves) from the egg white mixture as you're pouring it on.
Lower the oven because you'll essentially be drying the egg whites, to prevent burning. Once browned a bit, take the ready cake out and serve.