How are the onion and zucchini sliced for grilling?

Without much thought, I just sliced them into rounds--maybe 1/3" thick. That's simple for both the small, tender eggplant and the zucchini. My grilling friend then had to use a grill basket to cook them. No problem, really, and they're easier to eat that way--but if you sliced them lengthwise (said friend said), you could lay them right on the grill without the basket. In the end, I think it's up to the cook!

Based on the photo, I'd guess moretimeatthetable sliced the veggies about 1/2 inch thick. Just aim for a consistent thickness so they cook evenly.