Beef tendon still in bath over 72 hours. This part circled in red is not fork tender and tough, Should I take it out and just finish it by braising it?
Yes, at a high simmer for several hours. Seasonings optional.
Do I add any liquids or just dump whatever is in the bag. There’s some bag juice and the tendons.
braising normally calls for enough liquid to cover at least half the meat. Sorry, but my post clearly won’t reach you in time. But, a very simple braising liquid for beef starts with 50% beef broth and 50% red wine, add’l herbs added as you like (bay leaves, garlic, etc.). I have read that 180 F is needed to break down connective tissue, and tendon is pretty much pure connective tissue.