Place pork ribs into a large bowl. Add 2 cups of ice and cover with cold water. Set aside while you make the marinade (about 20-30 mins). In a large bowl, combine and whisk: 2/3 cup spicy brown mustard, 1 cup apple juice, 4 tbsps Worcestershire sauce, 2 cups packed brown sugar, 2/3 cup warmed honey and 2 tsps salt. Set aside.
Rinse ribs in cold water and paper towel pat dry. Place ribs into the slow cooker bone side up. Pour the marinade over the ribs and turn ribs to dip in marinade. Set slow cooker to “Low – 5 hours”. After 4 hours, check if the meat is coming easily off the bone. (Sometimes pork baby back ribs come less meaty and are ready in 4 hours while other times they are meatier and need to cook slightly longer).
Preheat oven to 400°F. Brush bottom of baking dish with barbecue sauce. With help of kitchen tongs, transfer cooked ribs to the baking dish. (Be careful as these will fall apart, so that you don’t get covered in hot marinade if pieces of ribs fall back into marinade once picked up). Brush ribs all over with barbecue sauce and cook for 10 mins. Serve hot and fresh.