This is a very simple dish that can have so many variations.  Preheat your oven to 450F, slice zucchini and toss in a bowl with enough olive oil to coat. Pour into a greased casserole dish or roasting pan, sprinkle with salt and pepper, cover and roast about 15-20 minutes.  Play around with adding additional vegetables (onion, yellow squash, etc.) or different seasonings.  You can top them with bread crumbs, parmesan cheese, etc. once they come out too.