Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel and slice the carrots into 1-inch diagonal pieces and cut the chicken breast into 1-inch bite-sized chunks.
In a large mixing bowl, whisk together the maple syrup, olive oil, sea salt, black pepper, and cinnamon until well combined.
Add the chicken and carrots to the bowl and toss thoroughly until every piece is evenly coated in the maple glaze.
Spread the mixture in a single layer on the prepared baking sheet, ensuring there is enough space between pieces for even roasting.
Roast in the oven for 20 minutes, tossing the ingredients halfway through to ensure the glaze caramelizes on all sides.
Scatter the chopped pecans over the tray during the last 5 minutes of roasting to toast them until they are fragrant and crunchy.
Remove from the oven, garnish with fresh thyme leaves, and serve immediately while warm.