Cooking exactly the right amount for one meal often takes almost as much effort as cooking a bit more, yet that little bit extra can make the following day's lunch far simpler to sort out. Planning for this in advance turns one evening's cooking into two meals without any real change to the routine.
Choose dishes that reheat well or that taste just as good served cold, since not every meal is suited to being eaten again the next day. A simple stew, a rice dish or a pasta bake tends to work particularly well for this kind of forward planning.
Set the extra portion aside straight away
As soon as the meal is cooked, it helps to set aside the portion meant for tomorrow's lunch before everyone starts serving themselves at the table. Otherwise it is easy for the extra amount to disappear into second helpings, leaving nothing left over for the next day.
Cool the set-aside portion properly before it goes into the fridge, and use a container that can travel easily if lunch is eaten away from home. This small step means the following morning requires almost no extra thought or preparation.
Over a few weeks, this habit builds into a reliable rhythm where dinner and lunch are planned together rather than as two separate problems. It becomes second nature to think, while cooking, about who will be eating the extra portion the next day.
With double portions planned in from the start, lunch stops being a separate task to worry about each morning. One slightly larger pot in the evening quietly takes care of the following day as well, with barely any extra effort involved.