Preheat your oven to 180°C
Separate egg yolks and egg whites
In one bowl whisk egg whites with half of the sugar until stiff
In another bowl whisk egg yolks with the rest of the sugar until pale in colour
Add melted butter, then oil, whisk
Add youghurt and sour cream, whisk
Add frlour with baking powder and lemon rind in three parts
Fold in egg whites in three parts
Carefully fold in one cup of cherries
Pour in a prepared tin
Carefully layer the remaining cherries on top of the batter
Bake for about 30 minutes in fan oven or until its nice and golden, with toothpick coming out not doughy
Take out of the oven, let it cool for about 10 minutes and put on cooling rack
When cool, dust with icing sugar and enjoy