Step 1

Preheat the oven to 355 degrees F/180 degrees C. Using a pastry brush and softened butter, butter, and flour, an 8-inch/20 cm round cake pan.

Step 2

mix flour and baking powder in a medium bowl. Pour the yogurt into a separate large bowl. Clean the jar to use it as a measurer. Add eggs, granulated sugar, and vanilla sugar to the yogurt and beat with a hand whisk for a few seconds. Add the oil and quickly mix. Fold the dry ingredients and vanilla sugar into the yogurt mixture and gently mix, just to combine. Please, don't overwork the batter! At this stage, add citrus zest or fruits, apples, pears, lemon zest, etc.

Step 3

Pour the batter into the prepared pan and bake on the middle rack of the oven for 30 to 40 minutes. A cake tester or the tip of a knife inserted in the center of the cake should come clean or with a few moist crumbs.

Step 4

Let the cake cool for 5 to 10 minutes before unmolding, then transfer to a wire rack to cool completely. Dust with icing (powdered) sugar if desired.