Harness the Sun for Backyard Solar Cooking
Make memories and meals while you watch your kids learn
Growing up in Texas, I definitely tested the "It's so hot you could fry an egg on the sidewalk" adage, but I only ended up with a gooey mess and a ticked off dad. And then there was the summer a few years ago when my best friend and I decided, while sweating bullets waiting out a customer lull at our ill-fated yard sale, to attempt again. Mimosas were involved, so honestly I don't recall much more than a bunch of laughs and, again, an inedible mess. Third time's the charm, right? With summer on the horizon and temps already pushing that 100 degree mark – and all signs pointing to sticking close to home and playing outside in small groups for the duration – I decided that my small human and I would make a real go of harnessing that beast mode sun energy to cook a meal (and leave our oven off). And hey, even if the coronavirus moves along its merry way, zombies are still definitely a possibility, which makes solar cooking a great skill to hone no matter what global catastrophe we're facing.
The options are nearly endless when it comes to DIY solar ovens, but since my partner in crime is 10, and he hasn't had an actual science class in who knows how long, we figured we'd opt for a pseudo-science fair project using a pizza box and household materials. Before we get started, let's be clear: My fourth-grader and I had no idea what we were doing, so don't go chasing raw chicken breasts with this thing. Please stick to the food that won't kill you if things go haywire. It's more about the memories than the meatloaf.
I picked up a few clean boxes in various sizes from one of our favorite pie shops (shout out to Local Slice). You'll also need clear plastic wrap (we use half of a gallon-size Ziploc bag), black construction paper, aluminum foil, scissors, clear tape, and a clear plate/dish. "You also need a sunny day," Milo reminded me to write. The primary joy in this activity is the conversational learning and excited running commentary: "I named the guy on the [pizza] box Jeff. Or Fred. Fred's a cool name. Hey, Mom! We should make pizza 'cause, ya know, it's a pizza box. Mamma Mia pizzeria! How about tortilla pizzas? I mean, they're simple and tasty and it's a good midday snack." Sold.
To assemble the oven, we cut a square in the middle of the lid, leaving the top edge of the square attached so it can fold up and out. Then, using the clear plastic, cover (as airtight as possible) the space the flap leaves exposed and tape it down, making a window. Cover the bottom side of the square flap with foil. Line the bottom of the box with black paper; roll up newspaper (it's a good time to clear out that mail bin) and tape it along the perimeter of the inside of the bottom, on top of the black paper to insulate. Upon completing the construction, my very blunt offspring said, "Yeah. So, Mom, I don't think this is gonna work. I mean, I hope it does, but look at it." Fair enough.
Next, to make the pizza: Use a toasted tortilla (so it doesn't get soggy), add sauce, cheese, and toppings. To make more than one at a time, use a bigger box and toast a stack of tortillas, hand over the ingredients and let the kiddo(s) take the lead, in cahoots with the sun. Note: This project is a great chance to sit back and watch a kid learn, soaking up vitamin D in peace, still knowing you've checked off science, snack, recess, and quality time with very little expense.
Set the pizza on the clear dish and place inside the pizza box oven and close the lid so that the clear plastic covers it. Prop up the foil flap on the outside so that it reflects the sunlight down into the clear window (we used a stick). Place the pizza box oven in the direct sunlight and wait. We opted for the back of my car since it had been sitting in the sun all day, unused (there's nowhere to go). Upon placement, I asked Milo again if he thought the thing would work; it was a much more hopeful tune: "UM, YES! I can practically see the cheese melting right before my eyes!" (That is not true.) We checked after 15 minutes, but it needed another 15. The tortilla pizza is ready when the cheese is all melted and you add some fresh herbs "to make it fancy. And, you know, pretend like you're eating salad even though it's actually just a pile of cheese."
If you really want to dive into the science, grab a thermometer and record the temps at intervals. It's best to time this during the heat of the day, when the sun is directly overhead. And look, let's be real: If it doesn't work, talk about why and what happened (blame it on the sun, OK?) and then finish off the melting process in the microwave and pat yourself on the back for trying. Ours proved successful by some stroke of luck, so when asked about advice he'd offer, Milo simply said, "Get ready to enjoy!"
And if all of this sounds a little too DIY for your taste, we also tried out a new professional solar cooker called the GoSun Fusion (www.gosun.co). Branded as "the world's first solar oven that can cook through clouds, and even at night, thanks to its hybrid electric power capabilities," it's actually pretty incredible. This option employs no fuel or open flames and has a cooking tray big enough to make things like lasagna and a solar version of tandoori chicken. (You can use raw chicken in this thing.) It's portable and the vacuum tube keeps the food moist but will still get those brown edges and toasted tops, and it (allegedly) retains nutrients thanks to the process itself. Milo correctly observed that it "looks like a very cool satellite." They've got a whole blog full of recipe ideas, but we opted to make campfire-friendly food (hodgepodge rocky road s'mores and a breakfast frittata with veggies) in preparation for the near future where we can return to our regularly scheduled camping fun.
We agreed to take this new tool anytime we go on an adventure, with his logic ("Just in case we need to pull over and make something to eat") squarely in line with his belly. But I'm just thinking about all the fun things we can solar cook together – in a pizza box oven or solar oven from outer space – before he's old enough to doubt my coolness.
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