Rinse 4 bone in pork chops with the majority of the fat trimmed and pat dry. Coat with 1 tablespoon olive oil and kosher salt & pepper, as desired. Allow to rest at room temperature for at least 30 minutes prior to cooking. Insert a meat thermometer into the middle of one of the pork chops.
Heat grill to medium high. Cook pork chops for 5-8 minutes on both sides or until internal temperature reads 145°F. Allow to rest for at least 10 minutes before serving.
While the pork chops are cooking, heat 1/2 cup balsamic vinegar, 1 tablespoon fresh rosemary(minced), 1 teaspoon 1-2 cloves fresh garlic(mined), and 1/4 teaspoon kosher salt in a small saucepan over medium heat. Allow balsamic to reduce by at least half, stirring occasionally. Once a thicker syrup forms, remove from heat and stir in 4 tablespoons butter to melt.
To serve, pour freshly stirred warm sauce over pork chops.