Preheat the oven to 400°F (200°C).
Season the pork chops:Pat dry with a paper towel and season both sides with salt and pepper.
Sear the pork chops: Heat olive oil in a cast iron or oven-safe skillet over medium heat. Sear pork chops for 2 minutes per side, then set aside.
Caramelize the onions: Reduce heat to medium-low, add butter and sliced onions. Cover and cook for 5 minutes, then add rosemary and stir. Cook for another 5 minutes, stirring occasionally.
Create the gravy: Pour in the white wine and chicken stock, bringing to a simmer. Gradually add cornstarch while stirring until the sauce thickens.
Add pork chops and cheese: Return pork chops to the skillet, top with Gruyere and Gouda cheese, and transfer to the oven. Bake for 10-15 minutes, or until cheese is melted and pork chops reach an internal temperature of 145°F.
Rest and serve: Let the pork chops rest for 5 minutes before serving.