I'm poor.
There is no 2 ways about that.
I'm single, unemployed, parent.
I get universal credit.
Once rent is taken off I'm left with £500 or there abouts.
Gas, electric, council tax etc. Once that's all gone, then I think about food.
I can technically cook a meal that costs 30p a portion, I can cook a meal that costs less.
Unfortunately it costs a lot upfront to do that.
So, let's say for arguments sake someone writes a recipe like:
Sausages 10p each
1/2 tin beans 11p
Cheese 30g 30p
1/8 garlic 5p
Herbs / salt / pepper (free in cupboard)
That's great and looks cheap.
But you can't get a single 10p sausage, it costs £1.20 for 20.
You can't buy 1/2 of a 50p tin of beans.
You can't buy a 30g slice of a £1.79 block of cheese.
You can't buy a garlic clove, a whole one costs 40p
So if you ignore that flaw, and the cost of cooking it..
2 sausages
1/4 sweet potato
1/2 tin of beans.
1/2 cup rice.
Cut up sausages, fry.
Cut up sweet potato, add to sausages, fry.
Sweet potato soft and cooked, pour over beans.
Cook rice.
Serve.
Cheap as you like, but upfront costs would be way more.