Scald the zucchini in salted water and then slice them.
Whisk the eggs and add the parmesan cheese and some salt.
Put melted butter in an oven proof pan.
Pour the egg mixture and zucchini in an oven proof pan (I would make sure the sides and bottom are coated with the butter, but that's not listed in the instructions).
Bake the tart at 200 C (roughly 390 F) for about fifteen minutes.