So many recipes call for caramelized onions including simple grilled steaks, burgers, and more complex recipes such as soups, stews and sauces. While caramelized onions are a commonly called for ingredient, the technique seems baffling for many home cooks. This technique will work for any onion but is especially delicious with spring onions as they are as sweet as candy when prepared this way.
You will need a heavy-bottomed sauté pan. This is not the moment to pull out aluminum cookware. Pull out the good stuff. The heat will be evenly distributed and your onions will be less likely to burn. You can also control the heat on a heavy-bottomed pan easier than on a thin aluminum pan.
You need neutrally flavored oil. I like canola oil or olive oil. I do not pull out my expensive extra virgin olive oil or my delicate nut oils for this. I need something that is going to stand up to serious heat.
You will also need a silicone spatula or tongs. Whichever works for you-just something to pull the onions out of the pan. Oh yeah, you need kosher salt and freshly ground pepper.
Here we go:
- Cut the onion in half lengthwise or flower end to root (not horizontally). Slice the onion with a sharp knife into thin strings.
- Heat the sauté pan over high heat until it is very hot. Add a thin coating of oil to the pan. The oil should be hot before adding the onions. To test this: see if the oil shimmers when added to the pan.
- Add a small handful of onions to the pan. Do not add too much. If you do, the hot pan will cool down too much and the onions will just steam. You only want to add enough onions to cover the bottom of the pan.
- Now leave the pan alone for a few minutes. Do not start stirring yet. You want the heat to build up on the onions and start caramelization of the natural sugars. When the onions start to brown, stir or flip them to brown the other side. Salt and pepper each batch while they are cooking.
- The onions are caramelized when they are dark brown, not black! They should still hold their shape and be very fragrant. Remove the onions and repeat with more onions until they are all caramelized.
The good news is that caramelized onions can be stored, covered in the refrigerator for up to 3 days.