Preheat & Prepare: Preheat your oven to 375°F (190°C). Lightly grease a baking dish with olive oil or line it with parchment paper.
Make the Honey Dijon Sauce: In a small bowl, whisk together Dijon mustard, honey, olive oil, apple cider vinegar (if using), garlic powder, onion powder, salt, and pepper until smooth.
Coat the Chicken: Place the chicken breasts in the prepared baking dish. Season with salt and pepper. Brush or pour the honey Dijon sauce over the chicken, ensuring each piece is evenly coated.
Bake the Chicken: Bake for 30-35 minutes, or until the chicken reaches an internal temperature of 165°F (74°C). Halfway through, baste the chicken with the sauce from the baking dish for extra flavor.
Serve & Garnish: Remove the chicken from the oven, let it rest for a few minutes, then garnish with fresh parsley or thyme. Serve warm with your favorite sides.