Preheat the oven to 400°F. Pat the chicken thighs dry using a paper towel and place them on a large plate.

Season both sides of the chicken thighs with salt and pepper, then set aside.

Heat the oil in a large cast-iron skillet over medium-high heat. Test if the oil is hot enough by touching a corner of the chicken skin to the oil; if it sizzles, it's ready. Once the oil is hot, place the chicken thighs skin side down in the skillet. Cook for 4-5 minutes or until the skin is crispy.

Once crispy, turn the heat down to medium. Using tongs, remove the chicken thighs, flipping them over to skin side up, and transfer them back to the plate. Discard the drippings, then return the skillet to the heat.

Add the butter to the skillet and melt. Next, add the minced garlic and dried parsley to the melted butter and sauté until aromatic, about 1 minute. Add the chicken thighs back to the skillet, skin side up.

Place the cast-iron skillet into the preheated oven and bake for 30-35 minutes (depending on the size of the thighs), or until an internal temperature of 175°F is reached using an instant-read thermometer.

Plate the chicken thighs with desired sides, then spoon the garlic butter over the tops. Garnish with fresh parsley and serve.