I love roasted vegetables, especially when they’re golden brown on the outside and tender, almost velvety on the inside. To guarantee such results, many chefs parboil the vegetables before roasting them. Parboiling gives them a head start toward tenderness in a moist cooking environment before being exposed to the hot, drying blast of the oven.
While I like those results, I don’t like the thought of two cooking methods that require different pans. After all, roasting vegetables should be easy and practically hands off. That’s where my method comes in. I realized I could create a similar moist environment right on a baking sheet by covering it tightly with foil for the first half of roasting. The hot oven plus the natural moisture in the vegetables creates steam, which gets the cooking process off to a gentle start. Then I simply remove the foil to let the dry heat of the oven coax out the vegetables’ natural sugars, concentrating the flavors and caramelizing their exteriors.
Though the vegetables are delicious simply seasoned with salt and pepper, I also like to add additional flavorings, such as herbs, spices, citrus zest, minced ginger, or garlic, but only after the vegetables are roasted. The heat of the vegetables is enough to bring out the flavor of the aromatics without burning as they might in the hot oven.
I usually steam and roast vegetables at 425°F, but for those with more moisture, like butternut squash, I’ve found that a hotter oven results in better browning. I also steam higher-moisture vegetables for less time and roast for longer, so they get longer exposure to the caramelizing effect of dry heat.
Since I first tried this method, I’ve never looked back. And my roasted vegetables have never been better.
Tips for Successful Steam-Roasting
• Use a large rimmed baking sheet, not a roasting pan; the lower rim will allow for better airflow and superior browning once the foil is removed.
• For easy cleanup when including a sugary component like maple syrup or honey, line the baking sheet with parchment. Otherwise, direct contact between the vegetables’ surface and the baking sheet promotes best browning.
• Extrawide heavy-duty foil makes easy work of completely (and tightly) covering a large rimmed baking sheet.
• Use tongs to lift the foil off to avoid the hot steam.
• Turn the vegetables once or twice after the foil is removed for more even browning.
• To keep the browned exterior intact when turning or serving, slide a thin spatula under the vegetables if they’re sticking.