Bake the onions and garlic (unpeeled), then peel and chop very finely.
Peel the zucchini and boil them about 10 min. in boiling salted water until softened somewhat.
Then, chop them very finely. You can put them in a blender but don't blend to a paste.
In a bowl, mix together the onions, garlic, finely chopped dill, grated feta cheese, zucchini (without the water they release), yoghurt.
Stir everything well and your antipasto is ready.