This recipe from King Arthur Flour is pretty quick. You really do need to salt and sauté the squash to keep from having a watery final product. If you follow these steps, you’ll end up with beautiful wedges. It’s also just as good at room temperature or cold.
My zucchini is grated, salted and sitting in a colander as I write.
If you like, use your leek as part of the chopped onion.