The Best Way To Reheat Caramelized Onions Is Also The Easiest
It's rare to find a dish that isn't improved by the addition of jammy, salty-sweet caramelized onions. Stir caramelized onions into your next pasta dish, plop 'em on a burger, incorporate them into your mashed potatoes ... the list goes on and on.
Pretty much the only thing that doesn't absolutely rock about these morsels of heavenly deliciousness is the prep work to make them. While you can add sugar to cook caramelized onions slightly faster, there's no way to get around the 45 to 60 minutes of hovering and stirring that's involved. That's why, when preparing onions this way, it makes sense to make a big, whopping batch of them and portion them out in your fridge or freezer for easy-peasy reheating.
Luckily, reheating caramelized onions is a lot easier than cooking them. While warming them in a pan on low heat is valid, there's a simpler, more hands-off, and altogether better way to do it: using the microwave. You've spent enough time cooking down the onions and making them taste amazing; reheating should be an effortless process.
A little technique leads to perfect reheated onions
Before you simply stick your caramelized onions in the microwave and hit some buttons, take a few moments to set yourself up for success. Microwaved onions, just like almost anything else reheated this way, can suffer from loss of moisture. Luckily, there's a hack to prevent this sort of drying out: Microwave a glass of water at the same time.
Heat your caramelized onions slowly. Put them on for 30 seconds, give them a stir, and pop them back in for another half a minute at a time. The stirring is essential. In the fridge or freezer, the fat will separate from the body of the onions, making them look funky. Stirring brings everything back together as the fat and onions are gently warmed.
Caramelized onions only keep around five days in the fridge, but they freeze well if you need to store them for longer. An airtight container will keep them fresh and ensure that, when they have a date with your microwave, they'll be as hearty and tasty as when you first made them.