This solar cooker is exactly the sort of thing I hope to do more of this summer and in the future. I made this a couple years ago on a mission trip to the Dominican Republic. I was hoping to show the locals (who have plenty of sun) how to use less charcoal and hopefully become more self sufficient. I was only there a week and left it with someone, no idea if it ever was used again.
There are plenty of solar cookers on the market but this one could be made for just a few dollars or even free if you found a big box and scavenged some foil. I painted a mason jar black on the outside but you could use a small black pot. A glass bowl or oven safe turkey bag around the pot or jar would certainly improve the efficiency of the cooker. Even with a “greenhouse” around the cooking vessel it still acts more like a slow cooker than a frying pan. With some forethought you can set your food out a couple hours before meal time. The risk of burning is slim, the stove just doesn’t get hot enough. I used it most for beans and rice. This summer I plan on building another one and broadening the food I cook in it. Keeping heat out of the kitchen in the summer is an additional bonus! Happy cooking!
Here are the plans for this cooker and many more on this site!