Broil pork chops 4-5 in. from the heat for 4 minutes. Meanwhile, in a small bowl, combine the sugar, cornstarch, salt and mustard. Stir in the butter and vinegar until smooth.
Turn chops over and broil for 2 minutes longer. Spoon about 2 teaspoons sugar mixture over top of each chop. Broil 2-3 minutes longer or until a thermometer reads 145°. Top each chop with 1 teaspoon pecans. Broil until pecans are toasted, about 1 minute longer. Let stand for 5 minutes before serving