Sprinkle the beef shanks with salt; set aside.
In a large Dutch oven or large heavy pot over medium-high heat, heat the olive oil. Add the salted beef shanks and brown on both sides until golden brown; remove from pot and set aside.
Add the onions and brown until golden; remove from pot and set aside.
Deglaze the pot with the red wine, reducing the wine to the consistency of syrup.
Reduce heat to low. Return the browned beef shanks and onions to the pot, sweating the meat and onion until they have released about 1 cup of their juices. Add 2 quarts of water and let simmer, partially covered, for 2 hours. Do not allow the water to boil.
After 2 hours, remove the meat to a plate and let slightly cool and then pull the meat off the shank bones. Remove any fat and muscle tissue from the cooked beef. Using two forks, shred the beef and set aside. Save the cooked beef for making Ropa Vieja - Cuban Beef Stew.
What is Ropa Vieja: Ropa Vieja literally means "old clothes" in Spanish. The name describes the shreds of meat (usually beef shanks) and vegetables which resemble colorful strips of rags. The beef must be cooked and shredded first. This makes an excellent filling for tacos, burritos, making taco bowls, and also served with rice.
Place the shank bones back into the pot. Add the beef consommé and let gently simmer, without a lid, for another 45 minutes.
After 45 minutes, remove from heat and strain the beef stock through a strainer into a large bowl.
Beef stock may be stored in the refrigerator for up to 3 days or frozen for longer storage.
Makes approximately 6 to 8 cups of beef stock.
* Select beef shanks with lots of meat on them. Do not trim excess fat from meat before cooking. You will remove the fat when you shred the beef.
** Consommé is slightly thicker and richer than beef broth. You could substitute with beef broth.
Homemade Beef Stock Recipe: https://whatscookingamerica.net/KarenCalanchini/BeefStock.htm