I don’t know why your husband decided to no longer eat at the kitchen canteen, but in our house, I became concerned with the amount of cured meat or pre-packaged cold cuts my husband was eating during the week for a quick way fix lunch.
Since it is not easy to get to a store whenever I want, and even harder to carry a lot of groceries home at one time, I now buy protein with the idea that whatever I purchase or make for dinner must also be something that can be eaten as leftovers for lunch. In our case, not every lunch is eaten away from home, so that makes it easier to reheat many dishes… But sometimes lunch needs to be transportable.
So I buy enough chicken or turkey breast that there will be enough left over to cube and make into a chicken salad. If I am cooking beans, I make enough to set aside for lunches like bean dips or bean salads. If I am cooking eggs, either its a bigger frittata that will have extra slices for a sandwich the next day or I will hard boil what I am not using to be used to make cold lunch. If I buy steak, it is a huge one, and cold sliced steak over greens is lunch in the coming days. If I am grilling bread slices for bruschette, I will even toast extra slices for lunch the next day. If I am making potatoes, extra ones are available to cube for a salad. Ditto grains like farro.
Whatever I cook, it’s my husband’s job to take the evening leftovers and assemble his own lunch out of them. There are always raw vegetables in the house like red pepper or fennel or carrots that can go into a salad or just raw into a lunchbox, and plenty of fresh and dried fruit, along with nuts, breadsticks and healthy crackers.
So basically my advice, focus on more or less doubling the protein being cooked in the evening. The only dinner for which there are no leftovers in our house is seafoods and fish.