Molly Baz of Bon Appetit tells us that it's not that easy to perfect the delicate art of roasting vegetables. Is that true? I've been perfectly happy with mine! Then, she describes the perfect roasted vegetable: uniformly golden brown, crispy exterior and just-tender interior. Yes, on occasion, I do get the perfect roasted vegetable but I just thought it was the state of the vegetable or how long I've left them in the oven that was giving me problems.
Apparently, if you have a convection oven, you can consistently roast vegetables perfectly. The convection ovens blow around hot air and wick away moisture and steam, which allows the vegetables to brown more quickly and evenly. Molly Baz say "Fear not: Whatever kind of oven you've got, the "had roast" is here to save you and your roasted vegetables."
So what is the "hard roast"? It's a technique that utilizes a very under-appreciated part of your oven—the floor. Essentially, you're turning the oven floor into a large, flat, high-heat burner, and your sheet tray into a large, flat sauté pan. When that sheet pan full of vegetables hits the super-heated oven floor—which, in most ovens, is where all of the heat comes from—they get an immediate hard sear which jump-starts the caramelization process, much as they would in a pre-heated sauté pan. Meanwhile, the ambient heat of the oven cooks them through, ensuring that they are tender throughout but not mushy. By the time they've softened just slightly, a deeply-charred crust has also formed. This technique works especially well for hearty, sturdy vegetables that can take an aggressive sear such as cauliflower, broccoli, leeks, turnips, mushrooms, beets, carrots, brussels sprouts, fingerling potatoes, green beans, cabbage, etc.
Here’s how it works:
Preheat your oven to 450°.
Cut your vegetables into equal sized pieces. The key here is to be sure all your vegetables are roughly the same size so that they cook evenly. Shape isn’t as important as consistency of size here.
Toss vegetables with the fat of your choice—olive or neutral oil, bacon fat, whatever—being sure all vegetables are evenly coated. Season with kosher salt and pepper. At this point, you can opt to include other spices or aromatics that will compliment your meal. Add a few sprigs of thyme and some smashed garlic, or toss in some ground cumin and coriander, or curry powder.
Toss these vegetables on to a rimmed baking sheet and place the baking sheet DIRECTLY ON THE OVEN FLOOR.
After 10 minutes or so use a spatula, spoon or pair of tongs and move the vegetables around a bit to encourage browning on all surfaces. You will notice that any part of the vegetable that is touching the sheet tray has developed a beautifully charred crust.
Continue to roast on the oven floor, taking a peek every 5 minutes or so until they are roasted and caramelized and just al denté. This will vary according to what vegetable, what size pieces you are working with, and what kind of oven you have. As long as you keep an eye on things, it won't fail you.