Nutrition per dollar numbers are a bit dubious. https://efficiencyiseverything.com/food-nutrition-per-dollar... Flour tends to beat everything since it is so cheap. For example, flour has 83.3 mg of iron per dollar. However, if you tried to hit your DRI for iron using flour, you would greatly exceed your daily caloric intake.

One could argue just using a vitamin pill for micronutrients, and optimizing protein/dollar for macros.