Sure, you can cook root vegetables in a microwave oven. But you end up with mushy vegetables and miss out on the crunchy bits, the best parts from roasting. So reach a compromise: Give the roots a head start in the microwave, then transfer them to the oven to crisp up, putting irresistibly crunchy vegetables within reach on an average weeknight.
• To work in advance, microwave the roots, toss them with the remaining ingredients, and set aside, loosely covered with a kitchen towel, for up to 4 hours.
• For the best results, use an 11 x 17-inch or 13 x 18-inch baking sheet so that everything can fit in one layer to make good contact with the hot surface.