Learn how to caramelize onions with this step-by-step tutorial! Caramelized onions add tons of savory richness to countless recipes.
You can use any type of onion (including leeks and shallots) with this method. I recommend using yellow onions for a neutral, balanced flavor.
Use a firm spatula or wooden spoon to scrape up the brown bits (as opposed to something like a rubber or silicone spatula). This one
is my personal favorite.