01 - Preheat the oven to 400°F and line a baking sheet with parchment paper.
02 - Place the carrots in a single layer on the prepared baking sheet.
03 - Whisk together maple syrup, olive oil, melted butter if using, sea salt, black pepper, and cinnamon in a small bowl.
04 - Pour the glaze over the carrots and toss to coat evenly.
05 - Roast for 25 to 30 minutes, turning once halfway through, until tender and lightly caramelized.
06 - Transfer to a serving dish, sprinkle with parsley if desired, and serve warm.