Due to COVID, I put most of my food at home in a spreadsheet to track inventory so I could figure out how much I had to buy on each shopping trip to last for a week or two.
At the moment I have 54938 calories of food on hand (not counting tomatoes, lettuce, and onions that I do not track because I only use them as sandwich toppings or for small salads where they contribute negligible calories).
This cost $171.44. That works out to $7.49 for 2400 calories.
Most of this is heat and serve stuff. E.g., there are some mini deep dish pizzas, some frozen breakfast sandwiches (think Sausage McMuffin clones), Hormel "Compleats" entrees, instant rice cups, add water and nuke mashed potatoes, canned soup, and such. Another big group is things for sandwiches: bread, sliced meats, condiments. An assortment of things that don't require any cooking or prep, such as protein bars and potato chips. Finally, ham steaks, liquid egg substitute, and frozen mixed vegetables.
It turns out I'm spending somewhere between 1/2 to 1/3 of what I spent on food pre-COVID. The interesting thing is that it is not a hassle. I always knew I could eat a lot cheaper if I cooked at home, but that also took a lot more time. But for most of what I'm keeping now, cooking is really just putting it in the microwave or in a frying pan for a while. That doesn't really take much time at all.
When COVID is done I will go back to getting take out--but only now and then for variety. I don't think it will ever go back to being my main food source.
I will probably gradually add more things made at home from lower level ingredients, which should bring the cost down some more, and can probably be done without adding much more time.