1. Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
2. In a small bowl, whisk together the Dijon mustard, maple syrup, olive oil, apple cider vinegar, minced garlic, salt, and pepper until well combined.
3. Place the chicken breasts in a resealable plastic bag or shallow dish, and pour half of the mustard mixture over them. Let them marinate for at least 15 minutes, or up to 2 hours for deeper flavor.
4. Arrange the marinated chicken breasts on one side of the prepared baking sheet. On the other side, spread the halved baby potatoes and carrot sticks evenly.
5. Drizzle the remaining mustard mixture over the vegetables, ensuring they are well coated.
6. Bake in the preheated oven for 25-30 minutes, or until the chicken is cooked through and the vegetables are tender. The juices should run clear, and a meat thermometer inserted into the thickest part of the chicken should read 165°F (74°C).
7. If desired, garnish with fresh thyme sprigs before serving. I love adding a sprinkle of fresh herbs for that extra pop of color and freshness.

As someone who enjoys experimenting, I sometimes add a dash of smoked paprika to the mustard mixture for a hint of smokiness, reminiscent of the flavors from our family barbecues.