I use a Cool Whip bowl year 'round. In winter I use the lid for heat retention when I need to put
my food aside to tend to something else. (Always happens)

And if you want more insulation nest it in a 2nd Cool Whip bowl W/ double sided tape on the bottom of the inner bowl to hold it together. That should insulate plenty while you're eating.

You can trim the top rim off the outside bowl with nail scissors for a better fit and even put double sided tape around the rim between the bowls.

Eric