FasterStronger - you're speaking to the coverted
but although those items are cheap, if you have none of them and your budget is already exceptionally tight, you wouldn't be able to afford more than one item per week or two. By the time you've got everything you'll have run out of the first item you bought. It's why whenever I have friends whose DC set up home for the first time etc I buy them a 'storecupboard' pack as a housewarming present (as well as something alcoholic, of course).
My essential store cupboard items are vegetable stock cubes, paprika (which I use in 90% of things as it really helps bring out the flavour in tomatoes), chilli flakes and chilli powder, coriander, basil (I prefer fresh as I use it in salads too, but dried is cheaper and needs replacing less often), salt, pepper, olive oil, flour, soy sauce and worcester sauce (I like thai fish sauce too, but it's more expensive and worcester sauce does the job). Also essential are fresh garlic and onions.
That's a fair bit more expensive. I also use cayenne pepper, mint, rosemary and sage, though I wouldn't consider them as essential as I only use them in certain foods.
I make my own wraps (don't like bread much), cook my own pastries when it's wild fruit gathering time, and generally eat very cheaply. I feed three of us on about £150 a month, which includes buying toilet rolls, washing powder, etc. However, it has taken me years to learn how to do this and I am constantly on the go (not at all uncommon for me to be making wraps after midnight while getting up at 6 the next morning), which is fine for me but wouldn't work for everyone.