In a plastic container put the salt, sugar, peppercorns, and mustard powder. Add the hot vinegar and swirl to dissolve. Let mixture sit for 5 to 10 minutes to develop flavor. Add ice cubes and shake to melt most of the ice. Add chops and cover with brine. Refrigerate for 2 hours.
Remove chops from container and rinse. Cut horizontal pockets in each pork chop for stuffing. Combine rest of ingredients, and put into piping bag that is not fitted with a tip. Pipe each chop full with cornbread mixture. Grill the chops on medium high heat for 6 minutes on each side. Turn each chop 45 degrees after 3 minutes to mark.