You do stir the onions occasionally while caramelizing them but not too often.
When caramelizing the onions you stir the onions every couple of minutes or every 2 to 3 minutes and you can also use tongs to turn the caramelized onions.
You should also allow the onions to cook and develop their flavor and texture without stirring them constantly and if you stir the onions too often it won't let the onions brown properly.
If the onions start to stick to the pan you should let the onions stick a little and brown and then stir them again before they burn.
If the onions do start to burn you should lower the heat to medium low or low heat and you can also add a bit of water if the pan begins to dry out.
You do cover the lid or cover the pan when caramelizing onions.
Covering the pan with the lid while caramelizing the onions will trap steam in the pan which speeds of the softening process and heats the onions much more quickly.
However lift the lid occasionally to stir the onions and check for any browning.
The reason why you should add vinegar to caramelize onions is because the vinegar adds acidity, flavor and also helps deglaze the pan.
The acidity of the vinegar when added to caramelized onions complements the sweetness of the caramelized onions and also adds a brightness and nuance.
Balsamic vinegar is a popular choice of vinegar for caramelized onions as it adds a bit of bite.
White vinegar is a more neutral tasting vinegar option that adds subtle acidity.
Caramelized onions are done cooking and caramelized when the onions have become a deep golden brown or dark brown color and tender.
Caramelized onions also take around 40 to 50 minutes to fully caramelize although the cooking time will depend on the type of onion you're cooking and how many onions you're cooking.
You can caramelize onions diced or sliced although when sliced lengthwise the onions when caramelized retain their shape better and result in slices with a subtle crunch.
When the caramelized onions are diced or sliced crosswise the onions will burst more cell walls and result in a softer and more spreadable consistency.
However the traditional and classic method of caramelizing onions is to slice the onions before caramelizing them.
The difference between caramelized onions and sauteed onions is the cooking time.
Sauteed onions cook for a short time until they are soft and possibly a bit brown.
Sauteed onions also have a mild onion flavor and also a slightly crispy outside and soft center and they are also often used as a base for sauces and soups.
Caramelized onions cook for a longer time in fat such as butter or oil, until the onions are soft and deep brown.
The natural sugars in the onions caramelize during the cooking process, which gives them a sweet, rich flavor and also a jam like texture.
Caramelized onions are often sued in dips, pastas, soups, on burgers and sandwiches and in sauces.
The best oil to caramelize onions is olive oil which has a lower smoke point than canola and is perfect for caramelizing onions.
To allow the caramelized onions flavor to shine you want to use a neutral oil which can be canola oil or grapeseed oil that also can withstand high heat without smoking.
Olive oil can also tolerate high heat and is a great choice for caramelized onions.
Butter is not ideal for caramelizing onions as it burns more quickly than olive oil although the butter does add flavor.
You can also use both butter along with olive oil and the butter will add flavor to your caramelized onions and the olive oils higher smoke point prevents the caramelized onions from burning.
When caramelizing onions you can also use a pinch of salt to draw out the liquid from the onions, which helps the onions soften.
To make caramelized onions at home start by heating the oil in a 12-inch cast iron skillet over medium heat.
Add the onions and sauté for 5 minutes, or until starting to soften.
Add the salt, reduce the heat to medium-low and cook for 50 to 80 minutes, stirring the onions every couple of minutes, or until the onions are very soft, golden brown, and caramelized.