Smoking chicken breast at 200°F (93°C) will take approximately 2 to 3 hours, depending on the size and thickness of the chicken breasts. It’s important to use a meat thermometer to ensure that the internal temperature of the chicken reaches 165°F (74°C) to ensure that it is fully cooked and safe to eat. Additionally, you may want to consider adding wood chips to your smoker to add flavor to the chicken breasts.