Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Peel the carrots and slice them into 1-inch diagonal pieces to ensure even roasting.
In a small bowl, whisk together the maple syrup, olive oil, apple cider vinegar, and half of the sea salt and black pepper.
Place the chicken breast on one side of the baking sheet and season both sides with the remaining salt, pepper, and dried thyme.
Toss the sliced carrots with the maple glaze mixture on the other side of the baking sheet until every piece is well coated.
Roast for 15 minutes, then briefly remove the pan from the oven and scatter the pecans over the carrots.
Return the pan to the oven for another 5 to 10 minutes until the chicken reaches an internal temperature of 165°F and the carrots are fork-tender.
Let the chicken rest for 5 minutes before slicing and serving alongside the glazed carrots and toasted pecans.