Remove the meat from each of the beef shanks.
Chop meat into 1-inch pieces.
Season the meat with salt and pepper.
Heat the olive oil in a large stock pot.
Add the beef and the bones to the pot.
Brown on all sides.
Stir for one minute, or until translucent.
Add 8 cups of water, more salt and pepper, and garlic.
Cover and simmer for 30 minutes, or until beef is tender.
Add jalapeño, bay leaf, chayote, zucchini, carrots, and corn.
Taste for salt. Add salt and pepper if needed.
Make sure there's enough water to cover all the ingredients. If not, add more water.
Cover and simmer for 50 minutes.
In last 10 minutes of cooking, add cabbage slices and lime juice.
Taste again for good measure.
Top each bowl with cilantro.
Serve along with additional lime wedges and tortillas.