I've been on a hunt for some good insulated containers I can use for lunches. Any recommendations? Would be great to have one for soups and one that's rectangular or square for other foods. Do those exist?!
For the rectangular or square insulated containers, do a web search for "insulated bento box" or simply type insulated food containers. I think Thermos makes these, might be other manufacturers. Problem you might encounter is the container is not microwaveable.
Rubbermaid makes a line called (unfortunately) Lunch Blox, modular sets which include cooler units. Can be used for sandwiches, salads, entrees etc. Some lunch bags too. I have not used these, but they look clever and have some good reviews.
I have packed lunches at various stages of my daughter's life. Different needs over 16 years. These aren't insulated but I really like Pyrex bowls & if you can rewarm in a microwave, they are great. They come in 3 sizes. They are round & come with lids. No issues with plastic. I have also used the lunch blox. They are good for keeping things cold. I have never had much luck with any product which is supposed to keep things hot for more than a couple hours. At 1 time I used Correlle plates which were divided, wrapped them in plastic wrap & were good for rewarming in a microwave. They just had to be kept level. I also had a bento box. It it wasn't suitable for the microwave. Good luck.
I would use a thermos for soup if you want to keep it hot. There are some with a spoon folded into the lid so you don't have to worry about remembering one.
We also have a small, probable 8oz metal, insulated food container from kleen kantene that my sinuses in his lunch box.