Whisk together canola oil, apple cider vinegar, garlic, salt, and pepper together in a small mixing bowl. You want to whisk vigorously until the marinade emulsifies. You can also do this by shaking all the ingredients together in a sealed jar.
Pound chicken thighs until they are an even thickness and pat dry with paper towels. Place in a Ziplock freezer bag, pour marinade into the bag with the chicken and move around until chicken is coated in the marinade. Squeeze the air out and seal the bag. Marinate in the fridge for 30 minutes to 3 hours. Remove chicken from fridge 30-40 minutes before grilling.
When ready to grill, remove chicken from bag and discard marinade. Grill over medium high heat (400–425°F) for 4-6 minutes per side or until internal temperature reaches 165℉.
Wrap chicken in foil and allow to rest for 5-10 minutes before serving.
