Prep - The day before, soak chickpeas in a bowl of salted water (or skip and use 2 cans of chickpeas). In a large pot, place chicken, beef, bones, bacon slab, ham slab, and sausages with 18 cups of water. Bring to a boil and skim off any foam. Add salt and pepper and simmer 1½ hours. Cool and refrigerate overnight.
Cook Chickpeas - The next day, remove meat pot and scrape any fat solids from the top. Transfer meats to a net bag or cheesecloth. Reserve 1 cup of the broth and ½ cup of the bacon to use for the meatballs. Drain chickpeas and add to pot along with meat bag, onion, garlic, scallion, carrot and potato. Adjust seasoning and simmer, covered, for 1 hour. Turn off heat.
Make meatballs (if using) - Add the reserved shredded beef, chopped bacon, and egg in a food processor and process until smooth. Transfer to a bowl and add garlic, parsley, reserved broth, salt & pepper, plus just enough bread crumbs so mixture can be handled. Form into sausage shapes, 2-inches long by 1-inch wide. Heat oil in a large skillet and fry meatballs on all sides until golden brown. Add meatballs to the liquid in the pot and turn heat to medium-low. Cover and simmer for 1½ hours.
Make Cabbage - Heat oil in a large skillet and sauté the onion and garlic until onion is wilted, approximately 5 minutes. Add cabbage, salt and pepper. Continue cooking over medium heat until cabbage is tender, about 20 minutes. Stir in wine vinegar and remove from heat.
Noodles (optional) - If using noodles in soup, boil them in a saucepan until just about done, drain, and divide between soup bowls.
Serve - Remove the bag with meats to one of the two platters you'll be serving them on. Strain the broth to a bowl or large Pyrex measuring cup. Ladle broth into the bowls with noodles, if using, and serve as the first course.Cut meats into serving sized pieces and arrange nicely on one platter. Add meatballs and cabbage around platter. On a second platter or big bowl, arrange the vegetables and chickpeas. Serve with crusty bread and hearty Spanish red wine.