Leave the zucchini whole. Do not trim them, just wash them.
Bring a large saucepan of water to boil and add the whole zucchini. Cook about 15-20 minutes. Don't overcook them or they'll fall apart. They should just bend a bit when you pick them up with a spoon.
Lay them on a wire rack or in a collander and sprinkle 1/2 teaspoon of the salt.
When you can handle them, trim the ends then cut each in half cross-wise and then cut into quarters lengthwise so you end up with 8 wedges per zucchini.
Arrange the wedges cut side up on a plate. Sprinkle the other 1/2 teaspoon salt over them, then pour the olive oil over the wedges. Sprinkle the lemon zest on.
Just before serving, squeeze lemon juice over the zucchini.