Chop onions, carrots, daikon radish, and can add thin slices of a pepper if you wanted heat. Set aside. In large stock pot, add oil, onions, carrots, ginger, radish, and spices and saute until onions are tender.
Add meat bones. Add enough water or broth to cover everything in the pot + 2" or so. Bring to a steady boil, then reduce to simmer for 5 - 6 hours or until meat is easily removed from bone.
Use a fine mesh strainer to strain soup liquid into a new pot. Set aside vegetables and remove meat off of the bones, set aside.
To just make the broth to use and store;
If you want to make this immediately you would continue to the rest of these steps, if you want just the broth then allow it to cool. Use a spoon to scoop up the fat that accumulates at the top of the liquid and discard that. Then you can pour into mason jars and store in the fridge or freeze once cooled.
To make pho immediately you would;
Add noodles to soup liquid and cook until al dente but tender. Add vegetables and meat back to soup liquid with cooked pasta. Fill bowls with soup, top with cilantro, green onions or chives and pepper slices if you'd like to add a bit of heat.