Start by preparing the smoker and preheating it to 225°F. While it is preheating, prepare the chicken rub.
Put the olive oil, lemon juice, minced fresh garlic cloves, dried rosemary, dried thyme, fennel seeds, salt, and pepper in a small bowl. Mix to combine and set aside.
Place the thighs flat on a plate. Baste each piece with the wet rub ensure both the front and back are covered. Set aside.
Once the smoker has preheated, place each piece of chicken directly on the smoker grates.
Insert a digital meat thermometer into the side of the meat until the tip is resting in the middle.
Close the lid and let the smoker do all the hard work.
When the internal chicken thighs temperature reaches 165°F, it's considered done.
Using tongs, remove the smoked chicken thighs from the smoker and put them on a dish. Cover with aluminum foil and allow them to rest for at least 5-minutes before serving.