Yesterday, I needed caramelized onions for a dish I was making. I had never caramelized onions before, even though it’s very easy. It’s also a bit time consuming. So it occurred to me that I should caramelize a bunch of onions at the same time, and freeze some for later use.

It also occurred to me that onions that are beginning to go soft, or that half an onion that’s in the refrigerator from last week, are perfect candidates for caramelizing. So I fished through the refrigerator and actually found two separate halves lurking in there. Then, I squeezed my whole onions to see which needed to be used first. I added a couple firmer onions, and cooked up the equivalent of five onions, even though I only needed a small amount for the dish I was making. The rest, I froze.

I love it when I discover a new (to me) way of limiting my food waste.

If you like this idea, here’s how to do it.


Caramelizing onions

  1. Slice as many onions into strips as you think your pan can handle.
  2. In a heavy bottomed pan, melt 1/2 teaspoon of butter or olive oil per onion over medium heat. Add the sliced onions, some salt and freshly ground pepper. Stir.
  3. Continue to stir once every minute or two until the onions reduce and turn a deep brown color, but do not allow them to burn. This should take at least 20 minutes or more depending on how many onions you have. Add a little more butter or oil during the process if you think the onions are getting too dried out.
Freezing caramelized onions

You can freeze all of the onions in one big bunch, but you might not want to use all of them at once. So here are some ideas for freezing small batches at a time.

  • Freeze the onions in ice cube trays or muffin tins. Once they're frozen solid, pop them out of the tray and store them in a sealed container. The smaller portions make it easy to use exactly what’s needed, plus the onions thaw more quickly in the pan. (via the Kitchn)
  • For perfect burger toppings, take a large cookie sheet and make believe you are topping a hamburger in a quarter inch thick and round manner. Place these "onion rounds" in the freezer Remove and wrap each in plastic wrap. Place in freezer bag and into the freezer (via Chowhound)
  • Place in a 1-quart freezer bag and spread out evenly and thinly, about 1/4 or 1/3 inch thick. Create creases in the bag from the outside with a long, thin object, like a chopstick. Freeze flat with the chopsticks until frozen. Then remove the chopsticks. The creases will give you the ability to break off sections of the frozen caramelized onions when needed. (via Secrets of a Kitchen Wizard)

I used my caramelized onions as a topping for flatbread. They are great as toppings on pizzas and burgers. Here are a few recipe ideas to use all those sweet, beautiful onions you’ve caramelized:

See also:

How to grow onions

Robin Shreeves ( @rshreeves ) focuses on food from a family perspective from her home base in New Jersey.

Onions getting old? Caramelize them.
Save onions from getting wasted and have caramelized onions ready when you need them.