Heat them too long and they may actually ignite.
NPR reported that some leafy vegetables, such as kale or spinach, can spark in the microwave. It can cause fires if sparks are allowed to continue flying while the food is being heated. There are safe ways to microwave leafy greens. You can purchase microwave-safe steam baskets.
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You can steam leafy greens by adding some water in a bowl that is microwave-safe. You should only do this in short bursts and open the door frequently to release the steam. You can also use a steamer basket on top of a pot with water.
Chinese takeout containers can often contain hidden handles
It may seem like a good idea to heat up leftover Chinese food in the microwave to save money and time, but it is not advisable. The little metal handles on most Chinese take-out containers are a common feature. Many people don’t even notice that they exist. This is metal and shouldn’t be placed near your microwave.
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It’s also a good idea to check the food you are heating, as some foods can be dangerous. For example, rice, mushrooms and certain meats. You should still eat the entire Chinese takeout at once, but that’s our opinion. If you must reheat it, make sure that the food is safe and use a microwaveable container.