Position a rack in the center of the oven and heat the oven to 425°F. Line a large-rimmed baking sheet with parchment.
Toss the carrots, turnips, garlic, oil, 1/2 tsp. salt, and a few grinds of pepper on the baking sheet. Spread in a single layer, cover tightly with foil, and transfer to the oven to steam for 15 minutes.
Meanwhile, combine the maple syrup and Sriracha in a small bowl.
Carefully remove the foil, rotate the baking sheet, and drizzle the vegetables with the maple mixture. Continue roasting, turning once halfway through, until tender and browned, 25 to 30 minutes more.
Discard the garlic cloves. Sprinkle the vegetables with the thyme, season to taste with salt and pepper, and serve.
nutrition information (per serving):
180, Fat Calories
10, Saturated Fat
1.5, Polyunsaturated Fat
1, Monounsaturated Fat
Photo: Scott Phillips