Let Pork Porterhouse sit at room temperature for 30 minutes.
Preheat oven to 425f.
Season pork with salt and pepper.
Heat a cast iron skillet on high heat and drizzle some oil. Once the oil is hot, sear the pork chops until golden brown about 2-3 minutes on each side.
Remove the cast iron skillet from the heat and transfer into the pre heated oven.
Cook for 8-10 minutes reaching 140 degrees internally.
While the pork is on the oven, slice some onions and saute until caramelized.
Remove pork from oven and let rest for 2 minutes. Place caramelized onions atop the pork chop.