This is never a problem for us. Usually I cook the recipes for 4 and as we are only two usually there is enough over for at least one of our lunches.
Today as we have both been at home our lunch was chickpeas with kale, which will be my lunch tomorrow and for dinner we are having muchroom risotto which will probably be enough for Stefan's lunch, unless he wants to cook something else, in which case it will be my Friday lunch. We are bad at freezing food though as it usually just do not taste as well if it is unfrozen.
Mushroom risotto almost done: