Dutch oven? I didn't think anything could actually be cooked in one.

00:18 here. 9:22 sounds like she does this more often than I do, so listen to her on the timing. I haven't done it in awhile.

I have been stranded before with underdone vegetables that needed more time, but those were potatoes and winter root vegetables, which take longer. For summer vegetables, I bet her cook times are a better ballpark.

I always put tomatoes in my roasted veg- they get caramelized and chewy- just delicious with other Italian-type veg like zucchini, eggplant, onion, mushrooms, garlic. Drizzle olive oil and sprinkle with thyme, salt, pepper. And now I know what's for dinner tonight!

Agreed use two cookie sheets. Check on the veggies after 15 minutes. 30-60 is way too long. I usually toss zucchini, squash, red onion and mushrooms with a bit of olive oil and roast in the oven. 15-20 min is all it takes at 400. I usually stir the veggies around 10 min and 15 min.

Thanks everyone!

To keep them firm, do a single layer and don't crowd them--give them a little room between them. If your group is really big, use two sheets.

400 is the right temp. How long depends on how many vegetables, which ones, how thickly sliced, how densely packed. I'd look for a recipe online, or plan on spending a lot of time flipping them and tasting them every 15 min. Could be anywhere from 30 to 90 minutes, depending. (If you're winging it, start early. You'd rather have them ready early, in which case you can just turn the oven down to 200 pr 180 and let them stay warm. If they're late, you have no choice but to wait them out. The other options are serve them al dente, or microwave them and ruin them--not really options.)

If you're like my DW and you like easy cleanup and pristine pans, use parchment paper (in addition to the oil). If you're like me and don't care, just toss with oil.

OP here, I want firm veggies and no meat so I guess I want to use a baking sheet and high temp which is no proble. I will hold the tomatoes. How long in the oven should I expect?

Do you want a firm, some-of-them-are-crispy roast? Or is it OK to be a maybe-mushy, mixed-in roast? For the former, roast on baking sheets. Roasting in a covered Dutch oven may give you the latter, esp. if you use a lot of moisture-containing vegetables.

Things that are going to contribute more moisture--tomatoes, zucchini (and related squash), sweet potatoes, eggplant if you don't sweat it first.
Things that are going to stay firmer--cauliflower, broccoli, brussels sprouts, carrots.

Onions (and to a lesser extent mushrooms) are funny--they have high water content, but it evaporates and they roast into something yummy, without gumming up the stuff you're roasting with.

Personally, I'd either go with brussels sprouts, bacon, shallots, garlic, and red chili flakes (generously drizzled with oil), or a mix of cauliflower with other stuff I like (peas, mushrooms, onions).
If you want to go the other way, tomatoes, zucchini, eggplant, onions and peppers--you've got ratatouille. Google it for the right herbs/flavorings.

I would do it on a sheet/cookie pan. You want a big single layer. I would do zucchini, squash, onions and peppers. No tomatoes. Toss with olive oil and salt and pepper. Hot oven - 400-425. Stir occasionally

We have a big group coming to dinner and I want something easy for the vegetables. Thinking of just cutting up several things for the Dutch oven. What vegetables should I choose (zucchini, squash, onions, peppers, tomato?), what temperature, how long to cook? I am only planning to add olive oil and herbs but should I add anything else (broth?).