Beef shanks work well. But remember, the reason for using shanks and soup bones was to make the meat tender enough to eat. And, they are well exercised muscles and so have strong bee flavor. But you can use oxtail,rump roast,Chuck, and other tough parts from thee cow. They al work if you can't find good beef shanks.
I brown my beef on all sides after seasoning with S & P, just like Andy. I always have extra beef broth on hand as I brown my ground beef with a lid on the pan to trap the writer pour it off and put the juice in the fridge. It gels from the collagen, and the fat rises to the top and hardens, ans so is easy to remove. I use that broth asit tastes really good.
After that, I put the meat and bones,with marrow,into my pressure cooker and let it cook under pressure for 30 minutes.I let the pressure escape,check the fluid level in the pot and add more broth if needed. I taste the broth and season accordingly.
With the meat and broth goes carrot, peeled and sliced,one onion, coarsely chopped, one celery stalk, washed and sliced, 2 cloves garlic, peeled and minced, and 3/4 lb. cremini mushrooms, chopped and sauteed before adding to the soup.
Place the lid back onto the PC, and bring it to pressure. Cook for 20 minutes and your soup is ready. Servewith a crusty, yeasty bread roll, with real butter, and apple pie for desert, hot of course with French Vanilla Ice Cream on the side. I love barley, and use it often.
Seeeeeya; Chief Longwind of the North