Wash the zucchini and grate finely, then squeeze out very well. Mix well with eggs, breadcrumbs, semolina, Parmesan and spices, then leave to steep for approx. 1-2 hours. Cut out patties with a large spoon and fry them in hot oil in a non-stick pan for about 3 minutes on each side.
Make a sauce out of the yoghurt and the herbs and spices, arrange the patties with it and serve.