The idea of cooking with the sun has long fascinated me. Who hasn’t heard the old idiom of a day so hot you can fry an egg on the sidewalk? As a child, I took those words to heart and once attempted to sear fish on a sizzling metal slide. Now as an adult, I live in Montana in a home with no air conditioning, and the thought of turning on the oven on a summer day sends me back to the idea of cooking outside with the sun, this time using a proper solar oven.
In it’s most rudimentary form, a solar oven is a black box with a clear lid and possibly reflectors to focus the sun. Besides being a completely environmentally friendly option that requires no fuel, one of the best aspects is it doesn’t heat up the house. It’s also a more forgiving method. I tend to be a distracted cook, particularly in the summer when I wander out into the vegetable garden and dash back inside to the smoke alarm.
To start, I tried to build my own solar oven out of a cardboard box using instructions similar to these—though without much success after I inhaled way too much black spray paint. So I ditched the DIY route and got a Solavore Sport, a small unit that easily fits into the car or can be set on the picnic table while I work in the garden.
My first experiment was a batch of chocolate chip cookies using my go-to recipe I’ve made countless times in my kitchen. Even on a warm day with high overcast skies, they took two hours to bake, coming out tasty, though I was missing that touch of browning that gives cookies that crispiness I love.
For my next dozen, I clipped on the reflectors to give baking time a boost, especially since the skies were still marginal with the sun dipping behind the clouds every few minutes. The minimum internal temperature for solar cooking is 180 degrees F, but for the browning effect, I waited until it reached 200 degrees F before setting the next batch of cookies on a baking sheet inside.
Once the cookies were in, I kept an eye on the thermometer, delighting every time the needle went up past 250 degrees F—and nearly panicking when the clouds rolled through and the temps fell below 200 degrees F, causing condensation to form on the lid. When things heated up again, the moisture disappeared. It took under an hour for the cookies to finish with the intermittent sunshine, and with the kids circling like sharks, even less for them to vanish.
Overhead clouds grew heavy during my next batch, so I was in no hurry to check the temperature while I worked in the garden. Then, suddenly, the clouds parted and intense sunshine poured down. I ran over to the solar oven to find very brown cookies in a 275-degree oven within 40 minutes. They weren’t burned, but they were crunchy—perfect with a glass of milk.