This colorful dish is dressed with olive oil, lemon, Parmesan, and salt. Use young squash for this recipe -- larger squash have too many seeds and are more fibrous.
Using a mandoline, very thinly slice the yellow squash into rounds and the zucchini lengthwise. Arrange the squash rounds and zucchini slices on six salad plates. Sprinkle the rounds and slices with salt and pepper, drizzle with olive oil, and squeeze the juice of 1 lemon over them. Very thinly shave the Parmesan cheese directly on top, and serve with the other lemon cut into wedges.