Well, until my latest attempt, my success-failure rate using dry beans was running pretty evenly. However, here is the original recipe that inspired what I eventually actually did.
First, I soaked the beans overnight, to help ensure that I wouldn't have to cook the beans a lot longer than indicated on the recipe, although the recipe only says to rinse the beans. I used onion powder in place of the fresh onion, used a 7-oz can of mild green chilies in place of the jalapeno pepper, used only about 3 teaspoons of salt, and did not add the (optional) cumin. I added a little water in the middle of cooking, but not much, and when time came to check out the finished product, the consistency was just right for tostadas with no need to add anything.
Although my children ate them, the only thing I would change is to use less chilies, and perhaps substitute a 4-oz can for the 7-oz can--there just seemed like there was a little too much in this batch.
One of the things I like about the recipe is that it is made in a slow cooker. If you look here, and enter solar oven in the search box, you will find directions on how to build one. A solar oven apparently works much like a crock pot. I haven't tried this yet, but the knowledge of how to put a solar oven together with such basic materials that are inexpensive could prove truly priceless in an emergency.
To recap: Beans: 1 Me: 2. Hey, at least my statistics are getting better. :)