So CNN has a crazy little thing on family meals for under $10.
I know, it is family meals, not for one, but still. The idea that a home cooked dinner for 4 that cost $10 is really cheap is a bit dicey. There are so many good, tasty, healthy meals that can qualify at that cost that it really isn't much of a hurdle to get over. In fact, go through and see that some include a glass of wine or shrimp and you know that they were far more concerned with a price that allowed luxury than they were with really keeping the cost down. Maybe that was the point but still...
Carrots (or bell pepper), celery, and onion are cheap and can serve as the foundation of a vast variety of meals: soups, stir fry, pasta dishes, salads. Carbs are almost always inexpensive too, and if you go with brown rice instead of white, sweet potatoes instead of regular, and other good grains like oats, bulgar (wheat), barley then you get good nutrition along with the calories. Protein is the pricey bit. Generally your options are legumes (beans, lentils--really cheap--peanuts less so) eggs, canned something (like tuna), or some deal on an already inexpensive cut of meat (pork shoulder, whole chicken/turkey), but on the other hand you don't need much protein in any given meal. One pound of meat is 4 servings worth. Cutting that meat into a soup with beans or lentils can make it go even further.
If you are looking for luxury in your meals you are not likely too concerned with cost because cheap meals can be very tasty without adding high cost ingredients.