The Worlds Best Chicken: Ingredients: 4 boneless, skinless chicken breasts, 1/2 cup Dijon mustard, 1/4 cup maple syrup, 1 tablespoon red wine vinegar, Salt pepper, Fresh rosemary....Preheat oven to 425. In a small bowl, whisk together mustard, syrup, and vinegar. Place breasts into 913 lined baking dish. Season with salt, fresh rosemary pepper. Pour mustard mixture over chicken, to coat. Bake for 30-40 minutes.