Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Peel the carrots and slice them into 1-inch thick diagonal rounds; cut the chicken breast into uniform bite-sized cubes.
In a small mixing bowl, whisk together the olive oil, maple syrup, sea salt, black pepper, and garlic powder until the glaze is emulsified.
Arrange the chicken and carrots in a single layer on the prepared baking sheet and drizzle the maple glaze over the top, tossing thoroughly to coat.
Roast in the center of the oven for 20 to 25 minutes, or until the chicken is cooked through and the carrots are fork-tender.
During the final 5 minutes of cooking, scatter the pecan halves over the tray to allow them to become fragrant and toasted.
Remove from the oven, garnish with fresh thyme leaves, and serve immediately while hot.