If you're looking for cheap, you just need to look at any national dish. They were all developed by poor people from necessity. In the Americas, it is fairly simple. Either it's rice and beans, or it's a stew with everything available in it --along with some starch. This pattern can be found from Roman gladiators to sumo players, too. It's really not difficult.
The problem is that people who have various types of foods available and can afford them, so they eat foods that are not locally produced. It's true that the lower cuts of meat are cheaper, but having the choice among beef, pork, lamb, and chicken is a luxury. That is, in the US. Maybe it's true in Europe, too, but I know that it's rare to find "pied de porc" on an American menu, but in Paris you can.
Eggs are cheap and available. Bee pollen is a great "food," but it's way more expensive than honey; and then there's royal jelly.
Garlic is great, but those white things in plastic net from China are scary to me. Ginger is also healthy. But, I think the spices came in because they made food tastier.
Anyway, go where you shop. Find the cheapest stuff, and then prepare it so that it tastes good. The latter is the art. But, it's like paella if you live by the sea in a country that loves sausage. It's how lobster went from being poor man's food or bait to being a delicacy. Learn to make soup (or chanko nabe, or feijoada). Use what's available.
"A man is rich when he has time and freewill. How he chooses to invest both will determine the return on his investment."