Preheat the oven to 425 degrees F.
Combine all of the chopped vegetables into a large bowl.
In a small bowl, whisk together olive oil, maple syrup, dijon mustard, rosemary, salt, and pepper.
Brush the chicken thighs with the marinade, and then pour the remaining over the vegetables.
Stir well to combine with the vegetables, and add another tablespoon or two of olive oil if needed.
Arrange the vegetables and chicken on a baking sheet.
Bake in the preheated oven for 35-40 minutes, until chicken has cooked through to 165 degrees F and vegetables are roasted.
Serve and enjoy!