Fill the shell with beans or metal pie weights. Bake until the crust is just beginning to brown, about 15 minutes. Remove from the oven and remove beans or weights. Remove from the oven and set aside on a wire rack. Using a Mandoline or vegetable peeler, very thinly slice one green zucchini and yellow squash lengthwise.
Place slices in a colander in a single layer, sprinkle lightly with salt.
Place colander in a bowl and set aside to drain for 30 minutes. Melt the butter in a large skillet over a high heat. Add the leaks and squash and season with salt and pepper. Cook until golden brown until still firm, about 8 minutes. Place salted squash slices in between double layers of paper towels.