Yes, hamburger gravel works perfectly :-) The "Beef" TVP looks just like as well. Same size, etc.
Sizes....you have a good point. I will start measuring out the finished meals :-) The soups are easy to do (2 cups water? Big bowl). I have been trying in the past year or so to have all the recipes uniform in how much starch is added (1 cup rice, 3/4 cup dry potatoes, etc). Still, my meal size is not the meal size of a grown man I can tell you that! (My son at 10 eats nearly twice as much as me now.....)