- vegetable oil spray (Nonstick)
- 9 tablespoons extra-virgin olive oil
- 2 tablespoons chopped fresh thyme
- 2 tablespoons fresh marjoram (chopped)
- 2 pounds yams (medium, red-skinned sweet potatoes, peeled, halved lengthwise, then cut crosswise into 1 ¼- to 1 ½)
- 1 1/2 pounds carrots (peeled, cut into ¾-inch-thick rounds, about 4 cups)
- 1 1/2 pounds parsnips (peeled, cut into ¾-inch-thick rounds, about 4 cups)
- 1 1/2 pounds rutabaga (peeled, cut into ½-inch pieces, about 4 cups)
- 2 red onion (medium-size, about 1 pound, peeled, root ends left intact, cut into 1/2-inch-thick wedges)
- 3 tablespoons balsamic vinegar
- 3 tablespoons fresh parsley (chopped)
- 2 teaspoons grated lemon peel
- parsley sprigs (Fresh)
- Position 1 rack in top third and 1 rack in bottom third of oven and preheat to 425°F.
- Spray 2 large rimmed baking sheets with nonstick spray. Whisk 6 tablespoons oil, 2 tablespoons thyme, and 2 tablespoons marjoram in large bowl.
- Add yams, carrots, parsnips, rutabagas, and onions and toss to coat. Sprinkle vegetables generously with salt and pepper and divide between prepared baking sheets.
- Roast vegetables until tender and brown in spots, turning occasionally, about 50 minutes.
- Whisk balsamic vinegar, remaining 3 tablespoons oil, 1 1/2 teaspoons thyme, and 1 1/2 teaspoons marjoram to blend in small bowl.
- Drizzle over the still hot roasted vegetables.
- Sprinkle with chopped parsley and lemon peel.
- Season with more salt and pepper, if desired.
- Transfer to platter; garnish with parsley sprigs.
- Serve hot or at room temperature.