I've done the cheap food trick recipes with friends to see how far our imaginations and creativity would take us. Amazing what you can buy and stretch into nutrtious meals if you have to. And we did sample everything we thought of, only a few weren't tasty. As for fresh produce, no matter where you live you can have a hydroponic garden anywhere in the house and grow lertuce, tomatoes, cucs, zuchuni, beans, peppers, etc.
Homemade soups with lentils, white or brown beans, lima beans, black beans, etc, all high in protein and very filling. Many variations to think of, all delicious.Just amazing what you can throw into a huge pot of homemade soup.
Buying in season and freezing or canning helps a lot.