I did this for real for a year or two and the need to not use anything you already have is wrong. Unless the person is coming in off the street - they have spices and other food in the house. I also ride the bus or walk to everywhere with rheumatoid arthritis so weight and distance were factors for me.

I used the grocery ads and got all cheap stuff thoughout the month as they had it on sale. I did many trips per week instead of 1 since I could not carry all that anyway. I don't eat processed food so I would get flour - not bread, for example (way cheaper in the long run).

And I most definitely used dollar stores. I was in California and got my organic produce at the dollar store! They also had a place called bargain market which had very cheap healthy food. My other good sources for food were Mexican markets, small grocery stores, and gas stations which sometimes have cheap organic food - yes, this is true in California!

Now I'm in Bangkok and eat like a queen for about the same cost - all street food and open markets now :)

Good luck with your week. It is not easy to be plopped down into that lower level food supply. It gets easier if you do it for a lifestyle. I was getting $187 a month and ate very well. I fed my adult son a lot too but he was not on my stamps, so it can be done.