Minimal nutritionally complete diet

In college, I vaguely recall my instructor mentioning it was possible to live on beans and rice alone. When put together, all the essential amino acids can be obtained. I've also heard that it is possible to live on brown rice alone though I'm not sure. From a Buddhist perspective, regarding choice of ingredients what is the minimum number of ingredients that one can get by and still be nutritionally complete, preferring plant and dairy sources, if possible. Recently a soy drink called Soylent has been available which claims to be nutritionally complete but I was hoping to find a natural, fresh alternative. It's also discussed on SE Skeptics . I do understand that eating the same dish every day can become bland, but it seems like the right thing to do from a Buddhism perspective, valuing simplicity. There is a research article on pubmed which used the Campbells Wellness plan but seems to take include non-vegetarian ingredients. An article on NPR takes on the issue but still leaves the reader guessing. http://www.soylent.me/ https://skeptics.stackexchange.com/questions/17347/is-soylent-a-nutritionally-complete-shake http://www.ncbi.nlm.nih.gov/pubmed/10491676 http://www.npr.org/blogs/thesalt/2012/05/03/151932410/man-cannot-live-on-rice-and-beans-alone-but-many-do