Season your pork with salt and pepper. Slice slits into any fat along the edge of the pork chop so that the pork chop doesn’t curl as you cook it.
Heat oil over medium-high heat in a large skillet. Add the pork chops and cook them until browned and just cooked through, about 3–4 minutes per side. Transfer the pork chops to a plate and cover to keep them warm.
Add vinegar, brown sugar, and fresh rosemary to the skillet. Stir, over medium heat, until the sugar has dissolved. Simmer until the syrup turns a dark amber color, about 10–20 seconds.
Add the broth, and bring to a simmer, stirring occasionally. Add the pear slices, ginger, and onions and cook, uncovered, for about 5 minutes.
In a small cup or bowl, whisk the corn starch and cold water together with a fork until the corn starch has fully dissolved. Slowly add it to the simmering sauce in the skillet and stir until the sauce has thickened. Reduce the heat to low and return the pork and any juices to the pan. Spoon the sauce over the pork chops and serve, topping with onions and pears.