You can get a 10 pound sack of chiken leg quarters for around four bucks, and you can get a ten pound sack of taters for around two. Flour, and little milk and some butter, and you have fried chicken and mashed potatoes, and you have enough of it for a long time.
Baked barbecue chicken can be made if barbecue sauce isn't too unneccessary a cost. Depedning on where you live/work, you can talk to someone who farms on the side, and chances are they will sell you a hog or a side of beef.
Taters are good raw with salt. Rice is cheap.
Peanut butter can be had realitively cheap.