Start out by preparing the Baby Red Potato (3 pound). Cut the biggest ones in half or quarters. If you can't find baby potatoes, you can still use larger ones and cut into bite-sized pieces.
Rinse potatoes in cold running water.
Place potatoes in a waterproof plastic bag or container. Pour in the Apple Cider Vinegar (4 cup) and ensure potatoes are covered well. Place in refrigerator for 8-10 hrs.
After the potatoes have marinated, pour off and discard all liquid. Place back in the refrigerator until ready to cook the dish. When ready to cook, preheat grill to 300-350 degrees F (150-180 degrees C).
Meanwhile, slice Bacon (5 slice) into small pieces.
In a large bowl, combine potatoes, Onion (2/3 cup), bacon, Dried Dill Weed (1/2 teaspoon) and Ground Black Pepper (1/4 teaspoon). Pour Italian Dressing (2/3 cup) on top. Mix until the potatoes are evenly coated with the dressing.
Pour potatoes into a 9x11 foil roasting pan (or equivalent size) and cover with aluminum foil.
Roast on the grill for about 1hr and 20 minutes, stirring every 20 minutes to prevent potatoes from burning. Check for doneness of potatoes by jabbing one with a fork, it should be soft and some browning on the outsides of the pan. If you like your potatoes on the saltier side, crack a little Sea Salt (to taste) on top before serving.