Well, I stick with the cheapest vegetables, like cabbage, carrots, onions. Cut/slice, freeze and use them in stew or wok.
I eat meat, but not alot and always the cheaper kinds like chicken or pork.
Alot of the cooking is based on rice bought in big bundles.
When something is on offer I always buy a good amount of it, hence some months its higher than $100 and some are lower. There are weeks I practically spend zero because I empty the freezer.
I get cheap spice and other things from abroad (have friends who enjoy traveling and my wife is Kenyan).
We love spice, don't eat out and cook everything from scratch.
I only eat an apple for breakfast and rely on heavy lunches, which are free at work.
:)