Way back in 1979. i had just bought my flat in London (for a massive £14,000 ) and I had little spare cash after paying the bills.
I found buying a large jont (eg a whole shoulder of pork) would give me a roast dinner on Sunday plus lunch sarnies hot evening meals until Wednesday, then some cheap stuff for the other 3 days. Cost about a pound per day (for comparison, beer was about 50p a pint then.

If I could stand beans on toast every day it would be a lot cheaper.