01 - Set oven temperature to 425°F and line a large baking sheet with parchment paper.
02 - Place carrots, parsnips, beets, and sweet potato into a large mixing bowl.
03 - Drizzle the olive oil over the vegetables, add thyme, sea salt, black pepper, and smashed garlic. Toss thoroughly to coat evenly.
04 - Spread the seasoned vegetables evenly in a single layer on the prepared baking sheet.
05 - Place the baking sheet in the oven and roast for 35 to 40 minutes, stirring once halfway through, until vegetables are golden brown and tender.
06 - Remove from oven and discard the garlic cloves if preferred. Serve warm, optionally garnished with additional thyme.