The #1 Habit To Break if You Want Better Roasted Vegetables

My whole adult life, I believed that vegetables only came one way: sad, wilted, and flavorless, with the steamer as their only cooking method. That is until a chef friend invited me over for a dinner party and pulled a tray of crispy-crunchy broccoli florets out of the oven, glistening with olive oil.

After that, I was a convert, a roasted-vegetable enthusiast. I was amazed to see that just about any vegetable could be transformed by a blast of oven heat: Brussels sprouts lost their infamous funk, carrots became candy-sweet, and cauliflower turned into golden nuggets with crispy edges.

But even with my newfound love for roasting, my results were hit or miss. Sometimes my chunks of butternut squash were perfectly caramelized, and other times, they slumped into a mushy mess. Determined to understand what was going wrong, I turned to Janet Cobb, a personal chef and instructor on Classpop!, who revealed that I’d been breaking the number one rule of roasting vegetables—and shared the golden ratio for getting them just right every single time.

How To Perfectly Roast Any Veggie, According to a Chef

Despite the aesthetic appeal of YouTube videos that show a rainbow of ingredients cramming every inch of a sheet pan, it turns out that won’t lead to a perfectly cooked meal. In fact, overcrowding can have the opposite effect on your vegetables.

“If the sheet pan is too crowded when roasting, the vegetables don’t roast, they steam. The water in the vegetables doesn’t have enough room to evaporate, so they become soft instead of crispy,” Cobb explains.

The reason is simple: When vegetables are packed too closely, they aren’t equally exposed to the oven’s heat. This results in uneven cooking, leaving you with a mix of burned bits and soggy pieces.

Crowding the sheet pan leads to disappointing results because each piece needs space for proper roasting. Vegetables contain water, and when packed too closely, this water gets trapped, causing them to steam instead of crisp.

Avoid Crowding These Veggies At All Cost

Vegetables with the highest water content, like tomatoes, zucchini, and mushrooms, are the most prone to steaming when crowded. Always give these veggies plenty of space to let the oven’s heat work its magic.

You don’t have to skip these high-water vegetables—just follow Cobb’s helpful hints: “While mushrooms have a high water content, if you brush or wipe them with a paper towel or cloth before cooking instead of washing them, you'll reduce the risk of them getting mushy. Also, waiting to salt mushrooms until they are cooked will help them retain water rather than release it, keeping them firm. For zucchini, squash, and mushrooms, cutting them into chunks rather than slices reduces surface area, which also minimizes water release.”

Tips for Making Extra Crispy Roasted Vegetables

Now isn’t the time for low-and-slow. Instead, aim for a higher heat of 400°F to 425°F to ensure a major crunch factor, especially on fall favorites like cauliflower, Brussels sprouts, turnips, broccoli, cabbage, winter squash, potatoes, kohlrabi, and beets, plus hardy greens like collards, chard, and kale. A layer of aluminum foil with a generous glug of olive oil can help prevent sticking and encourage browning on the bottom of each piece.

Finally, ensure there’s enough room around each vegetable for hot air to circulate. Cobb suggests at least half an inch, or about a pinky’s width, between pieces. If your oven has a convection setting, use it—or even consider an air fryer—to maximize airflow and achieve the crispiest texture possible.