The question came into the website asking how a person who is limited in capabilities and rarely gets to the grocery store could be on the diet. Below is my answer:
How about bags of frozen vegetables, canned vegetables, frozen chicken breasts, turkey breasts, and frozen fish, bags of rice and potatoes as your main foods? Also rutabaga, turnips and parsnips are coated in wax so they keep. You can roast them and they make good fillers. All you would have to do is to boil or bake to have a meal. There are a lot of combinations in the bags of frozen vegetables, so you would have variety. Following this diet, you would also be free of eggs, which can be very troublesome. The advantage of following this is that you would not have odd ingredients snuck in by the preparers. Actually, as I look at it, the above would be very effective and would fit with your requirements that the food last for a month and would be easy to fix.