Preheat oven to 400°F. Gather all ingredients.
In a medium bowl, whisk together vinegar, 1 tablespoon olive oil, mustard, ½ teaspoon salt, pepper, garlic, ½ teaspoon rosemary, onion powder, and smoked paprika. Add chicken and toss to coat.
Place potatoes on a rimmed baking sheet; toss with remaining 1 tablespoon olive oil, ½ teaspoon salt, and ½ teaspoon rosemary. Place chicken on baking sheet with potatoes.
Roast chicken and potatoes 35 to 40 minutes or until chicken reaches an internal temperature of 165°F when measured with a meat thermometer and skin is golden brown. Let rest 10 minutes before serving.
