We are big fans of oven-roasted veggies in our little house...er...bungalowhold. I find that as long as you pick vegetables with similar densities it always works out well. What I mean by this is that if you are going to roast brussels sprouts, fingerling potatoes, and cauliflower, stay away from tomatoes, bell peppers, and summer squash. Otherwise you will end up having perfectly cooked veggies mixed with severely over or under-cooked ones.
There are a couple of things that must happen for this to be a success. Once you have chosen your veggies, heat your oven to 400 or 450 F - really hot. Next, wash, dry, and cut your veggies into uniformly sized pieces. After that, toss them in some extra virgin olive oil. Then lay the veggies out on a sheet tray but don't overcrowd them! If you overcrowd the pan you wont get wonderfully crusty and caramelized edges on everything and someone will be disappointed when they don't get the "good" pieces (you know exactly what I'm talking about).
Before you pop your sheet tray into the oven sprinkle everything (liberally) with kosher salt and freshly cracked pepper. If you want to get fancy, now is the time, you can also add fresh herbs or garlic to the tray. Roast the veggies, in my case, brussels sprouts and sweet onions, until they are golden brown and delicious which is usually about 20 minutes but every oven is a little bit different so just check them every 10 minutes until they look ready to eat.
Once you pull them out from the oven, finish them off with a squeeze of fresh meyer lemon juice for brightness and balance. It's pretty ridiculous how tasty these are after such a simple preparation.