Preheat the oven to 180 °C. Grease a shallow rectangular cake pan and sprinkle with breadcrumbs.
Wash the cherries, remove the stalks and pit them.
Cream the butter with the sugar, vanilla sugar and salt until light and creamy. Add the eggs one at a time and mix well. Stir the butter-egg mixture until a combined mass is formed.
Then sift in the flour, cornstarch and baking powder. Finally, fold in the cherries and about 2/3 of the chocolate chips. Pour the batter into the prepared pan, smooth the surface and sprinkle with the remaining chocolate chips.
Bake in a hot oven for about 40 minutes until golden brown. Then let cool and cut into cubes before serving.