Prepare chicken and place in a large, covered bowl or a large ziploc baggie.
Combine oil, garlic, seasoning; squeeze in the juice of the lemon, then slice it in about 4 large slices and throw in also.
Pour marinade over chicken and massage in to chicken (I loosen the breast skin, without removing, and rub some under there as well).
Let marinate overnight, or at lease a couple of hours.
Heat a large cast iron skillet over medium high heat.
Remove chicken from marinade and season all over with salt and pepper, then place in hot skillet.
Weight chicken down with another cast iron skillet (you can use any type of skillet, if necessary, and weight THAT down with cans or bricks or something).
Cook 10 minutes, then turn over and return weight; keep cooking 10 minutes and turning until chicken is crispy and cooked through, about 20 to 25 minutes (will register 165 degrees F on an instant read thermometer).