[LeifCarrotson]

Flour is at the top of the list with over 4000 calories per dollar, though obviously you need to bake it with something, and not coincidentally, white bread is next on the list with about 3000 calories per dollar. Bags of granulated sugar are also up there, and then the first things you can just boil and eat start to appear with rice, plain oats, ramen, and pasta providing about 1500-2000 calories per dollar.

In comparison, fast food like a 2-liter bottle of Coke or Pepsi provides about 450 calories per dollar, while a fast-food hamburger provides about 100. While the corn syrup lobby and fast food industrial systems are strong, they're not even close to being a cost-effective way to feed yourself.