Grandma Radka's Sponge Cake

First: all products should be at room temperature.

1. Beat 3 eggs with 1 1/2 tea-cups of sugar.
2. In a thin stream, while stirring constantly, add 1/2 tea-cup of oil.
3. Add sifted flour (sifted at least twice / 2 1/2 tea-cups) gradually - a spoonful at a time, sprinkled.
4. Finally add 1 tea-cup of yogurt with 1 level teaspoon of baking soda dissolved in it.
5. Flavourings as desired: vanilla, lemon essence....
6. Stir well and the batter is ready.

If you want it marbled inside, set aside 1-2 tbsp of the mixture, add a little cocoa, stir, and using a tablespoon make the pattern inside the batter with spiral movements. Naturally, it should already be poured into the tin.

Bake in an oven preheated to 175°C. Do not open it for the first 20 minutes. Be careful not to jolt it while working with the oven, so the cake does not sink. (Then I baked it another 30 min because I was using the cake collar. Bake it in a large tray!!! This collar is small.)

!!!!! Many years ago I used an oblong tin about 35/10/10 cm, as far as I remember, because it was thrown out long ago. In it I could make the pattern and it turned out a wonderful cake. Then I started baking it in a round pan about 28-30 cm in diameter. There it did not rise high, but baked better. The temperature at first at 180 degrees, then at about 150, for a total of about 40 minutes.

But every oven bakes differently; my ovens, the ones I've had, are not like yours, I never had a fan. If it doesn't work now in a small and deep tin, next time bake it in a round tray. It is thinner, but it is baked through. The cup I measure with is 250 ml.