Baking is a fine example of what solar cooking can deliver in the UK. This is a lazy and unique way to craft your daily bread. With amazing results. Let me show you how I do it:
Like all things solar you want to start early. In our case the night before. Mix your living yeast with flour and all other ingredients. Follow your own recipe, I have mine, it changes. Cover and leave your mixture overnight to rise (you know you’ve got sun tomorrow, right?).
Morning…now you want to catch all the rays so set out your Gorilla Sun Oven early, it will do a slow warm up in the weak morning sun. With a bit more flour knock back your dough and shape. Its got to be oven sized – baguettes, bagels, baps – whatever you can get in there. Let it rise for half an hour or so. Make sure you can lift it easily, to transfer onto your hot baking tray for a quick insert, I use baking paper for convenience.
Now for some solar cooking theory. This is not a fuel hungry wood-oven with hot stones and excessive heat. Its a glass tube. A very special glass tube. Protected by a super insulating vacuum the inner wall gets plenty hot from the sun, but theres not a lot of wall. It heats the air inside and also conducts to what you’re putting in. You have to conserve the heat because it takes time to warm up. The distance from the sun is 93 million miles, and then clouds get in the way, so don’t expect miracles! 
Quick as you can, pop the bung, remove the hot tray and carefully position the bread. Bear in mind it will rise further in the tube (‘bread spring’). Get it back in and secure the bung, which needs to remain loose but not fall off, repeat ‘not fall off’.
Now relax, go swimming, hot yoga, sunbathe, whatever you do. Don’t be tempted to look inside, don’t waste heat – its just the sun, it needs your help. Do nothing. Or if you want, adjust it after an hour by keeping the long axis at right angles to the sun. 5 seconds work, max.
1 hour – bread smelling steam is escaping, air temp inside is over 100°C
2 hours – its kind of done (Maillard reaction happening) 140-165°C
2½ -3 hours – crispy brown crust, patisserie in you garden kind of thing (if you did it right and the sun came out to play)
Disclaimer: This method only works with a solar vacuum tube oven in our UK sun. Times approximate. I’ve tried most other solar cooker types here and they just don’t cut it yet, for this application.
Author: Stewart MacLachlan, London – ‘Solar Bake Meister UK’
Pictures taken and bread baked between December 2016 and June 2017 in London, UK 51’30 North. Visit our shop section if you’re interested in a tube or other cooker. Help spread the word!
Copyright Stewart Maclachlan 2017