Thinly slice the apples into 1/4-inch wedges and the red onion into half-moons, setting them aside. Pat the pork chops dry with paper towels, then season both sides generously with kosher salt and freshly ground black pepper. Dry meat is crucial for achieving a good sear, which will develop flavor through the Maillard reaction.
Heat 1.5 tablespoons of olive oil in a large skillet over medium-high heat until it shimmers. Once hot, carefully place the seasoned pork chops in the pan and sear for 3-5 minutes per side without moving them around—this allows a flavorful crust to develop. Transfer the cooked pork to a clean plate and set aside. I like using thick-cut pork chops because they stay juicy in the center while developing a beautiful exterior crust.
Add 1 teaspoon of olive oil to the same skillet and add the sliced apples and red onions. Sauté for about 4 minutes, stirring occasionally, until the apples begin to soften and the onions become translucent. Add the sage, rosemary, and thyme, stirring constantly for about 30 seconds to release their aromatic oils. In a small bowl, whisk together the chicken stock and Dijon mustard—the mustard acts as an emulsifier and adds a subtle tang that complements the pork and apples beautifully.
Pour the stock-mustard mixture into the pan with the apples and onions, then use a wooden spoon to scrape up any browned bits from the bottom of the pan—this is deglazing and captures all the flavorful fond. Season the liquid with 0.75 teaspoon salt and 0.5 teaspoon pepper. Return the seared pork chops to the pan, nestling them among the apples and onions. Reduce heat to medium and simmer for 2-3 minutes until the pork is cooked through and the liquid reduces slightly, creating a light pan sauce.
Remove the skillet from heat and stir in the apple cider vinegar, which brightens the sauce and adds a final layer of flavor complexity. Taste and adjust seasoning if needed. Divide the pork chops among plates and spoon the apples, onions, and sauce over the top. Serve immediately while everything is still warm.