In a mixing bowl, combine the garlic powder, onion powder, paprika, sea salt, and black pepper until evenly mixed.
Place the chicken thighs in a large resealable plastic bag, add the avocado oil, then pour in the seasoning mixture.
Seal the bag and shake or massage it until each thigh is well coated in oil and seasoning.
Refrigerate the coated chicken for at least 1 hour or up to 8 hours to let the flavors penetrate.
Preheat your smoker to 375°F (about 15 minutes). Arrange the thighs skin-side up on the smoker grates, leaving space between pieces for air circulation.
Smoke the thighs for about 45 minutes, or until an instant-read thermometer inserted into the thickest part reads 165°F.
Remove the chicken from the smoker and let rest briefly before serving.