Place the ribs in a large baking dish and cover with almost all of the Coca-Cola (leaving about ½ cup of Coca-Cola for the BBQ sauce) and add the salt. Marinate the ribs for 24 hours in the fridge.
Heat the oven to 350°F.
Remove the ribs from the liquid, place on a large baking sheet and pat them dry. Sprinkle them with the chili powder. Pour 1 cup of water into the baking sheet, and cover tightly with foil. Bake for 2 hours, until the meat nearly falls off the bone.
While the ribs are in the oven, prepare the BBQ sauce. Heat the oil in a small pot over medium heat. Sauté the onion until soft, about 5 minutes and add the garlic, stir to combine. Add the ketchup, brown sugar, Worcestershire, apple cider vinegar, cayenne, and remaining ½ cup of Coca-Cola. Simmer for 15 to 20 minutes, or until the sauce thickens. Remove from the heat, adjust salt if needed and let cool. Once cooled, transfer to a high-powered blender and blend for 60 seconds until smooth.
Once the ribs are cooked, remove from the oven and heat an indoor or outdoor grill to medium high heat. Liberally brush the ribs with BBQ sauce. When the grill is hot, cook them for 7-8 minutes on each side until slightly charred. Remove from grill and add more sauce if desired. Serve immediately with extra sauce on the side.
Using Coke in the marinade AND the sauce means these ribs are so sweet and delicious.