Lunch is a simple concept. Stop work in the middle of the day and eat something that will keep you going and in good shape until dinner. It really needn't be more complicated than that.
I grew up in a frugal household. I was never hungry, but I know my parents struggled for many years to keep the household in the black. Things changed for the better for them in my teens and later, but early on we didn't have much. I remember running bare foot across particle board floors because they couldn't afford carpet in the house as a child. I had never seen a full closet of clothes until my early adulthood. The house was always so cold at night and I can remember shivering in the dark. To this day, I have many careful rituals to feel good at night. Fortunately, I have a caring husband who makes sure I am comfortable and warm.
For lunch, we often had canned soup and half a sandwich. Campbell's soup was the main brand then and there were much fewer choices. I liked cream of tomato and chicken noodle. I remember helping to make the soup, opening the can, spooning it into the pan. Back then Campbell's soup was concentrated. It came out in cold, jellied, chunks, not very appetizing, really. You filled the empty can with water or milk and poured into the pan, then heated and mixed the liquid with the soup. As it heated, it combined and started to look more like soup. I can still smell it as I write this.
We never felt deprived by these meager lunches. In fact, I think back fondly to these memories. We grew up feeling safe, cared for, loved. There are better soups available these days, but I still keep a few cans of the old ones for days when I need extra comfort.
Grilled cheese was another favorite for us. I remember my mother buttering the bread on both sides, taking out the cast iron skillet, slicing the cheese. I remember hearing the sizzle, the sound of my mother sliding the spatula under the sandwich and flipping it over, the smell of the toasting gooey mess and knowing warm comfort was coming. She was more than a bit of a perfectionist. She cut it just a certain way, it needed to be browned just so. Absolute heaven.
Lunch is a very simple thing. It needn't be hard. I understand that cream of tomato and grilled cheese is not your comfort food. So do something else! It needn't require standing in a line, ordering, paying. It isn't rocket science, just food.