Crispy Fried Onions are a terrific topping on many different foods. Indeed, I can’t imagine serving an Indian Biriyani without including crispy fried onions on top of the dish, and you can also find them being added to many rice, meat and vegetable dishes in India, Indonesia, and a host of other Eastern cuisines.
In the West, crispy fried onions are widely available commercially either in the form of flakes or ‘strings’, and they are often used on burgers, in sandwiches, and scattered over salads, baked potatoes, and cooked vegetable dishes. The commercially packaged varieties are, unfortunately, often tasteless or stale, but it is easy enough, if a little time-consuming to make them yourself at home.
How to Make Crispy Fried Onion
The secret to producing a good crispy end result is to slice your onions as thinly as possible. Ideally, they should actually be thin enough to be almost transparent.
If you want long ‘strings’ rather than ‘flakes’ you may wish to remove the center of each onion (as you can see on the upper onion half in the above picture) and reserve it for other uses.
A large amount of onion produces a fairly small amount of fried product, so be aware of that when estimating what you need. Luckily, once fried, onion keeps quite well so making large amounts (4 – 5 pounds at once, for example) is a good idea. Here, though, I am making just enough for just a couple of uses, so one medium onion is sufficient.
There are different methods for making crispy onion strings. Some merely involve deep frying raw, unadulterated onion slices, while others actually coat the slices or pieces on flour before frying. My method is a bit more involved but, in my opinion, it produces a quicker and better result.
To begin, toss your thin onion with about 1 teaspoon of salt per cup or so of slices. This may seem like a lot of salt, but most of it will be rinsed away later. Allow the onion and salt to sit for about 30 minutes or so until the onion is soft and has thrown off a good deal of liquid (as seen above).
After the above treatment, rinse the onion shreds in several changes of cold water to remove the excess salt and then squeeze dry to remove as much liquid as possible. Once done, lay the shreds out and let sit to dry a bit further.
This process, by the way, is essentially the same method for making my Sweet Onion Shreds (except, of course, that they are used raw, rather than being dried and later fried).
To fry the onion, heat deep-frying oil to a medium, or medium high heat, and then add the shreds. For a small amount, say… one or two onions worth… you can cook everything at once but, otherwise, it is best to work in batches.
When you add your onion, the oil will bubble and froth and you will see a lot of steam rising from your pot. You need to cook until the steaming stops and the excess water from the onion has evaporated. Depending on the size of the onion pieces and how thoroughly they have been dried, this will take a goof 20 to 30 minutes.
Once the pot stops steaming, the onions will begin to turn golden. From here, the cooking process will happen very quickly so keep a weather eye on the process. Once the first few strands start to brown, the progression from just done to burned in short order, so be prepared to act quickly.
At the appropriate moment, drain the shreds and blot free on paper towels. As soon as they cool, they will crisp up and you can use them immediately. If not intended for immediate use, you can store in a a dry container for a week or two or, if desired, in the freezer.