Here at The Kitchn, we're big proponents of frozen vegetables. While we do try to reach for fresh vegetables when we can, there's no denying the convenience and affordability of frozen, which is why we always have a few bags stashed in the freezer.
Growing up, the frozen vegetables I ate had been cooked in the microwave until mushy and limp, which is a shame because now I'm of the opinion that the best way to enjoy them is actually by roasting. As it turns out, frozen vegetables also have the ability to cook up just as nice and crispy as fresh do in the oven. The secret is an easy, three-step method that ensures roasted perfection every time.
1. Preheat your pan with fat.
You want your baking sheet nice and hot before those frozen vegetables get tossed onto it. This allows the vegetables to defrost almost immediately on the hot pan and start cooking. Just stick your baking sheet in the oven with a drizzle of olive oil or coconut oil while the oven preheats, and it will be ready for you once the oven is to temperature.
2. Roast in a hot oven.
Just like fresh vegetables, frozen vegetables need a good amount of heat in order to get caramelized and perfectly roasted. So don't be afraid to crank up your oven to 450°F to roast frozen vegetables. The high heat also helps to quickly evaporate any lingering condensation that might be on the frozen vegetables so they'll roast instead of steam.
3. Use plenty of fat.
Toss the frozen vegetables with a tablespoon or two of olive oil or another vegetable oil like coconut before spreading them onto the oiled baking sheet. You want the vegetables to be completely coated with thin layer of oil. This not only ensures that they'll cook and crisp up evenly, but it infuses flavor into every bite. Don't forget the shower of salt and pepper once they come out of the oven.
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