A microwave oven is a genuinely useful tool for reheating chilled or frozen foods, but it has a few pretty serious limitations. The first, and most important, is that it doesn’t heat evenly. That’s especially true when you’re heating foods with add-ins, like the vegetables, cheese and meats that usually fill a quiche. They all heat differently in the microwave, so it’s easy for one thing to overheat before the other is even warm.
A second issue is that microwaves take away the crisp texture of your crust, leaving it limp, soggy or even gummy. It’s possible to work around the issue of even heating, but the crust is trickier to manage.
Reheat a Whole Quiche
Eggs are especially delicate and hard to reheat in the microwave without overcooking them. The larger the portion, the more care you’ll have to take to reheat it gently, so a whole quiche requires your undivided attention while it warms.
Set the quiche on a microwave-safe plate, ideally with a sheet of paper underneath to help absorb any steam that comes from the crust. Set your power level to no more than 50 percent, which will help reduce the risk of any areas of the quiche overheating. Start by heating the quiche for 2 to 3 minutes, depending on its thickness; then let it rest for 1 to 2 more minutes so the heat can disperse evenly through the filling.
Continue reheating in 30-second increments until the filling is slightly hotter than serving temperature; then let it cool for a few minutes before slicing.
Reheat Quiche From Frozen
If your quiche was frozen rather than refrigerated, you’ll need to take the extra step of defrosting it first. Most microwaves have both a “defrost by weight” function and a “speed defrost” function, which works by time instead. Either one will work. Choose the time or weight suggested in the owner’s manual if you still have it, or just check every minute or two as it defrosts.
Once the quiche is at least halfway defrosted, blot up any surface moisture that may have appeared during the thawing process, and reheat it as you normally would.
Reheating Single Portions
Reheating a slice or two of quiche or one or two individual mini-quiches is easier to get right because they reheat more quickly. The relatively small quantity of filling won’t be as susceptible to hot and cold spots, and there’s less moisture to make the crust soggy.
Follow the same basic process, setting your microwave to 50 percent power, but start with no more than 1 minute of heating time for a slice from a full-sized quiche and 40 seconds or so for a mini-quiche. Once it’s hot, let each portion rest for at least a minute or two before serving.
Stack the Deck in Your Favor
If you know in advance that you’ll reheat the quiche to serve later, you can do a couple of things to help yourself out. One of the most important is to avoid ingredients like watery “city hams” or moist zucchini that will shed lots of moisture as they reheat. Stick to drier alternatives instead, like crisp bacon or well-drained cooked spinach.
You can also avoid the issue of soggy, disappointing crust by simply preparing your quiche without it. The filling itself will solidify where it meets the hot metal or ceramic of the quiche pan, especially if you dust the interior with grated Parmesan cheese after you grease or oil it.
Alternative Heating Methods for Quiche
Ideally, you’d really only use your microwave to heat a quiche in times of dire need. As long as you have a few extra minutes to play with, heating up quiche in the oven or toaster oven is a much better alternative. At 350 degrees Fahrenheit, a full-sized quiche can be ready to go in 12 to 20 minutes, depending on how deep it is.
Individual slices, or mini-quiches, can take as little as 5 minutes. For those smaller portions, a quick-heating toaster oven can be more practical than warming up your main oven. As a bonus, it’ll bring less heat into your kitchen on those hot summer afternoons.
Another less-obvious option is to heat the quiche in a skillet on the stovetop. Use a heavy-bottomed pan over low to medium heat, and cover it. The direct heat from below will crisp up even a limp crust, and the combination of conducted heat from below and the trapped heat from above will heat the filling gently and effectively in just a few minutes.