1 pound sweet potatoes , cut into 1 ¼-inch cubes
¾ pound carrots , cut into 1 ¼-inch pieces
¾ pound parsnips , cut into 1 ¼-inch pieces
1 hard squash , seeded, cut into 1 ¼-inch pieces
1 large red onion , peeled, with root end left intact cut into ½-inch wedges
¼ cup extra-virgin olive oil
3 tablespoons balsamic vinegar
2 tablespoons maple syrup
1 tablespoon fresh thyme leaves or rosemary
Salt and pepper
Nonstick cooking spray
Preheat oven to 425°F. Spray an extra-large, rimmed baking sheet (20×15), or 2 large ones (18×12), with non-stick cooking spray.
Place sweet potatoes, carrots, parsnips, acorn squash, and red onion in a large bowl. Add olive oil, vinegar, syrup, and thyme. Season generously with salt and black pepper. Toss to coat.
Spread vegetables on prepared pan(s) in a single layer. Roast uncovered 40-45 minutes until vegetables are softened and browned, stirring every 15 minutes while baking.
Can be made 3 hours ahead. Transfer to clean baking sheet and let stand at room temperature. Rewarm at 375°F for 10-15 minutes.
Uniform Size – Cut vegetables in similar sizes as best you can for even cooking. You can chop your veggies 1-2 days before roasting. Store in the fridge submerged in cold water and covered with plastic wrap so they don’t turn brown. Drain and pat dry when ready to roast.
Oil – Vegetables should be well coated with the olive oil mixture so they crisp up and don’t stick to the sheet pan.
Pan Size – Use large enough baking sheets with a shallow rim so the veggies can be spread in an even, single layer. If piled together in a higher-rimmed casserole dish, they will steam rather than caramelize.