Cooked chuck steak (eye roast cut, not sure if this translates to USA) for 50 people. 24 hours at 56C (132.8F). Removed cooking juice for sauce, cooled, resealed and stored. The day before reheating, I cut the cold steaks into serving pieces and rebagged. Steaks were reheated at 56C for an hour prior to a flash fry on each side on a pan on a commercial cooktop.
Steaks were cooked with salt and pepper as well as green peppercorns. Sauce was made from heated and strained cooking juices, chicken stock and 3 1/2 bottles of well made merlot. Reduced by half, simmered some cut carrot and celery in there for a little while then added thyme to infuse while it was cooling. Strained sauce and then thickened to sauce consistency with potato starch (one of the diners is gluten intolerant). Sauce was livened up with a bit of sherry vinegar.
Served with roasted smashed potatoes, cooked on onion in chicken stock with honey glazed carrots.
The majority believed it was fillet steak and wondered why it had so much flavour.