Reduce heat to medium-low. Add shallot to the pan and cook, stirring, until softened, about 1 minute. Add brandy and cook, stirring and scraping up any browned bits, until most of the liquid has evaporated, 1 to 2 minutes. Remove from the heat; stir in sour cream and the remaining 1/4 teaspoon salt. Serve the pork chops with the sauce.