I also love to roast broccoli and cauliflower, although I don't slice them. Instead I cut them into bite-sized florets, toss in olive oil, salt, and pepper, and spread on a baking sheet to roast. About 20 minutes at 450 is all it takes. Then remove and grate on some Parmesiano Reggiano, and a touch of cayenne if you like heat. A little lemon zest at the end adds a lot too.
