How to chop tearless onions, and 9 other genius microwave hacks
Ask not about the limits of your microwave, but about its endless possibilities.
PopSci is spending September relearning how to eat. As intuitive as our love of chowing down is, a lot stands between us and optimal eating. This month, we’ll break down diet myths, unlock delicious kitchen hacks, and explore our most common misconceptions about our grub.
Microwave ovens are so commonplace that it’s hard to imagine you’re missing out on tremendous cooking potential every time you pop in some leftovers, set it, and forget it. But you are. They don’t do anything that, say, a conventional oven or a stovetop can’t do, though they can do it faster, more efficiently, and with way less hassle.
But first, how do microwave ovens work
I’ll make this quick, I promise.
The heart of your microwave is called a magnetron—a bulky component made of a vacuum tube and two magnets. Its sole purpose is to emit, well, microwaves. Every time you reheat that delicious day-old pizza, the waves enter the oven’s inner chamber and travel across your slice. As they go, they excite water molecules and make them vibrate. This movement releases energy in the form of heat, which cooks your food from the inside out.
Microwaves are not perfect, though. As you might have noticed the last time you tried to nuke a hefty plate of rice, they don’t always warm up your dinner evenly, leaving some bits cold or undercooked, and others extremely hot. This is because—just like all waves—microwaves have peaks and valleys where their power fluctuates.
Tips to get the most out of your microwave oven
Now, what you came here for. Prepare to save time, wash fewer dishes, and get more deliciousness out of your foods.
Dry some herbs
Sure, you can go to the grocery store and get a bottle of dried basil, rosemary, or oregano. But if you have an abundance of fresh herbs, you can preserve them by using your microwave to dry them. Wash the leaves and thoroughly pat them dry—if there’s any water left on them, you’ll cook them, and you don’t want that.
Take four or five sprigs, put them between two sheets of paper towels, and heat them in the microwave for two to three minutes on high power. If they need further drying, keep going for another 30 seconds. When they’re done, take them out, let them cool, and use your fingers to break the leaves. Store them in an airtight container.
The quick spurt of heat has an effect similar to blanching, which preserves the color and aromatics of your herbs. The water in the leaves evaporates rapidly due to the effect of the microwaves, rendering perfectly dried flakes you can use year-round.
Get up to the last drop of citrus juice
Before you make orange juice or lemonade, give your fruit a 20-second spin in the microwave.
The heat softens the juice-holding membranes, so you’ll get more juice when you squeeze them than you would from room-temperature fruit.
Pro tip: Before using the microwave, roll your unpeeled citrus on the counter while applying light pressure. This will loosen the membranes even more.
We’ve had enough reasons to cry over the last two years. Onions will not be one of them.
Before you slice into the natural equivalent of a tear gas canister, microwave it for 45 seconds. The bully that makes you tear up every time you chop onions is a sulfur derivate called syn-propanethial-S-oxide. This chemical irritant stimulates your eye-lubricating lacrimal glands, and as a result, you start to cry. But less than a minute of heat in the microwave neutralizes this compound, so you can focus on dinner.
Heat up two dishes at the same time
A somewhat of a classic nowadays, and perfect if you’re having company for leftover dinner, is heating up two dishes in tandem by placing one toward the edge of the turntable, and the other one on top of a mug or an upside-down bowl. This second story will make the most out of the space inside your microwave and save you some hustling.
It won’t save you a lot of time though. As I mentioned before, microwaves are not perfect and sometimes leave cold spots in your meals, or fail to penetrate all the way to the center of denser foods. And this is in a normal setup. Having an irregular one might make it harder for your microwave oven to cook your dishes evenly, so you should give it an extra minute or two to make sure no one gets stuck with a cold meal.
Who needs knives when you have a microwave?
Since we learned how to smash garlic cloves with the side of a knife to peel them, our lives have been easier. But microwaves will make you forgo blades entirely (at least for garlic). Just put the cloves you’ll be using into your microwave and heat them up for 15 to 20 seconds—the skin will come right off.
The principle is simple: the heat produces steam when it contacts the water molecules inside the garlic, separating the skin from the flesh.
Something similar happens with tomatoes. First, wash your tomatoes and cut an X shape with the tip of a sharp knife on the side of the fruit opposite the stem. Microwave them from three to five seconds and pull on the corners of the X to remove the skin.
The microwave: the best appliance for solo living
If you live by yourself, chances are that you’ve wanted to bake a cake or a batch of cookies but decided against it because you’d have no one to share your sweets with.
I’m not here to tell you you can’t eat an entire cake by yourself, but whenever you want just one slice, you can make a mug cake. These sweet treats are single-serving cakes you can prepare without preheating the oven or dusting off your baking equipment—a microwave will suffice. You can choose chocolate, vanilla, experiment with other flavors, and even try a cookie in a mug. The best part is that you won’t have to scrub baking sheets or cake molds afterward.
If you’re into more savory stuff, maybe you’d like to cook a potato—that is, without boiling any water or having to wash a pot afterward. First, poke your spud with a fork to allow for even cooking and prevent any explosions. Then, put your potato (one, two, more—you do you) in a microwave-safe glass or ceramic bowl with some olive oil, salt, the dried rosemary you made before, or whatever other aromatics you’d like to add. Heat up your taters for five minutes on high power, and when that’s done, carefully take them out of the oven (it’ll be hot!) and turn them over. If you’re only cooking a single potato, microwave it for an extra three minutes, but if you’re eating more than one, do a second five-minute round, and enjoy.
The double-duty paper towel
This is a fairly well-known microwave hack, but if you haven’t heard of it, boy, do I have a treat for you: Next time you heat up a dish, get a paper towel, dampen it with some water, and put it on top of your food.
This serves two purposes, and the first one is pretty obvious if you’ve ever stuck your head inside the microwave and looked up (Have you? It’s gross). The paper towel will prevent your food from splattering all over the inside of your microwave, so it stays clean for longer. A damp paper towel will also help retain some of the moisture in your food so it cooks more evenly, and doesn’t dry out and become chewy.
Keep your microwave oven squeaky clean
If you haven’t taken a look at the inside of your microwave in a while, go look. You’re likely to find disgusting food scabs all over it. Let’s get rid of them with the power of citric acid.
Slice a lemon in half and squirt some of the juice into a microwave-safe bowl with about an inch of water. Toss the lemon halves into the bowl (make sure the water doesn’t cover them) and microwave them for three minutes on high power, or until the water comes to a boil.
[Related: Get old tea and coffee stains off your mugs]
When the time is up, leave the bowl inside—the steam from the water will carry the lemon juice and its precious citric acid cleaning powers to every corner of your microwave, while the heat will loosen up any dried gunk living inside. After five minutes, open the door and carefully remove the bowl (it’s probably still hot). Then use a clean rag or paper towel to wipe the ceiling and sides of your microwave. Don’t forget the turntable and the door, which are almost definitely also pretty gross.
If there are any stubborn stains or food build-up that resisted the citric steam, a degreaser can be your best friend—spray it on a clean rag and go to town. Just make sure that you use a clean paper towel with some water to remove any residue before the next time you heat up your food.