There was once a time when after I cooked a meal if there was just a small portion left I would scoop it into the trash and go on about my business. Those days are done, now I use everything. If there is a small portion of tuna casserole left instead of going into the trash it goes into a small single serving tupperware container. Typically this ends up being the perfect size for my lunch. Not only do I not waste dinner but it saves me money on the back end with saving money on lunch.
I know this may sound like common sense to most but when I think back to how many “lunches” I have thrown away over the years and the dollar cost associated with it, the number ends up being hundreds per year.