Okay, I just added corn to my brunch.
I put three halves of frozen corn in my other 48 ounce Thermos, salted it and added boiling water. Put the lid in and now will wait and when the steak is cooked I will have a nice brunch if this system works as well as touted. It will lower the cost of cooking, but that is not my goal. I like the idea of spending a few minutes preparing and then forgetting about it until eating time.
Look for a later post telling how the steak and corn fared.
I don’t think this is going to work for you. In a closed system, ignoring heat loss, you have added 140 degree water and a below room temp mass. These temperatures will normalize at some point, as some average of the two, depending on the mass of the meat and the water. However based on this the final temp of the meat can’t reach 140. I would guess at the end of the process you will have steak that reached approximately 80 degrees. Math isn’t really my specialty but a quick guesstimate would be 38oz of boiling water would cause 12oz of mostly thawed steak to reach 140 degrees in 1 hour.