Chop Vegetables Into Small Pieces If You're Roasting In A Rush
Maybe you're roasting a hunk of beef and forgot to add the vegetables, or maybe you just need a tray of roasted vegetables pronto, for guests who are already at your house, sipping an aperitif — either way, you need them ready in as little as 20 minutes. That seems like a challenge, since classic vegetables for roasting (potatoes, carrots, sweet potatoes) can take upwards of 30 minutes to roast, and quite a bit more if you want them to get nice and crisp.
But there's one shortcut that can speed things up substantially: Dice those veggies into much smaller pieces. The math here is pretty simple: If you cut a potato into 20 small pieces instead of eight larger ones, there's more surface area exposed to the heat. The pieces are also not so thick, so the heat can cut through to the center faster, slicing precious minutes off the roasting process.
What to look out for when using this trick
Although the "chop 'em small" method is handy, it's not foolproof, and you'll want to pay attention to a few factors. The faster cooking process means there's much more risk of overcooking or burning thinly cut vegetables. It's fine to use a recipe for guidance — for example, for seasoning or figuring out what temperature the oven should be set to — but roasted vegetable recipes may be written with larger veggie pieces in mind. So, don't just set a timer for 40 minutes because the recipe said so; you'll have to be more proactive and keep an eye on the oven, taking the veggies out when they appear cooked.
Secondly, small pieces will dry out faster, so you may have to make a decision about whether you want your veggies crisp (but potentially a little on the dry side) or pleasantly moist and cooked through (but not deliciously caramelized).
Finally, make sure your veggies are chopped evenly. If there's too much variation in size, you might end up with small pieces burning, and larger pieces not fully cooked.
Go turbo-speed with fast-roasting veggies
Chopping your veggies small is just one way to roast faster — and it's a far more reliable method than, say, turning up the heat on your oven and hoping it speeds up the process (warning: This may just make them overcooked on the outside and raw inside). But you can make things go even faster by choosing vegetables that just don't take so long to cook.
Some great options are softer, more summery vegetables like zucchini, red peppers. Skinnier veggies like green beans and asparagus are also relatively fast, as are cruciferous veggies like broccoli: most of these can roast in as little as 10 to 15 minutes. To speed things up, it's still a good idea to cut them into small pieces, and this is especially easy with skinny, stalk-shaped produce like asparagus and green beans, since you'll probably only need to cut them lengthwise. Tomatoes and mushrooms are also faster to roast, but they contain more moisture that might leak out onto the pan (especially tomatoes), so if a crisp, browned tray of roasted vegetables is what you want, they might not be so ideal. Unfortunately, if you're working on this kind of ultra-fast time frame, you may need to sacrifice some of the slower-cooking classics like potatoes and carrots, since getting them roasted in 10 minutes (even if they're finely diced) is not going to be realistic.