I disagree with this suggestion. One, the human body does not readily digest beans. Two, rice is a pretty heavily refined food, and white rice especially has been stripped of most of its nutritional value (http://en.wikipedia.org/wiki/White_rice).

From the perspective of spending minimal time, I suggest the unintuitive solution of learning to use slow cooking techniques. Most slow-cooked food is fire-and-forget: quickly prepare the ingredients, start the heat source, and get back to your hacking. Three hours later, you have several dinners' worth of excellent food.

Example: A simple beef stew takes about twenty minutes to prepare. Chop up about 1.5 lbs of beef into small pieces, dice one onion, mix with 1.5 lbs of unpeeled (but properly washed and scrubbed) fingerling potatoes cut in halves. Mix with salt and some water in an enameled cast iron 5-quart Dutch oven. Put in a 375-F oven. Return in three hours. You now have about three days worth of dinners. Improvise with spices as you see fit.