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Caramelized onions add an incredible depth of sweet, savory flavor to any dish. Whether you’re topping burgers, adding them to sandwiches, or using them as a base for soups or sauces, learning how to make caramelized onions is a key culinary technique.
The process of making caramelized onions is simple but does require patience – rushing it will just leave you with sad, undercooked onions without that rich, jam-like consistency and deep flavor. Follow this quick, step-by-step guide to get perfectly caramelized onions every time.
Summary
- Unbeatable Flavor: The long, slow cooking process allows the natural sugars in the onions to intensify and caramelize into an incredibly rich, sweet, and savory flavor you just can’t get any other way. They add amazing depth to any dish.
- Easy to Make: While it takes a bit of time, caramelizing onions is pretty straightforward. With just a few simple ingredients and some patience, you can make restaurant-quality caramelized onions at home.
- More Nutrients: Caramelizing concentrates both the flavor and the nutrients in onions. That means you’ll have even more beneficial antioxidants and compounds like quercetin than you would with raw onions.
- Versatile Ingredient: They are flavor-packed and can enhance everything from burgers, sandwiches, and pizzas to pasta, soups, dips, and more.
Ingredients for Caramelized Onions
- Onions: Yellow, white, or sweet onions like a Vidalia onion work best for caramelizing.
- Olive oil: A few tablespoons of olive oil will be used to cook the onions.
- Sea salt: To balance the sweetness of the onions.
How to make caramelized onions
- In a large cast iron skillet, add the olive oil and raw onions. Saute the onions over medium heat for 5 – 6 minutes or until they begin to soften.
- Next, sprinkle the salt over the onions and stir. Reduce the heat and let it cook slowly for 20 minutes. then lower the heat again and let it sauté for another 30 minutes.
- Stir the onions every frequently until they take on a jam consistency.
Recipe Notes and Tips
- Use a wide sauté pan or Dutch oven with a heavy bottom to ensure even cooking. Cast iron or stainless steel works great.
- Slice the onions thinly and evenly – about 1/4 inch thick max. Thick slices will take much longer to caramelize through.
- Be patient! Rushing the caramelization by cranking up the heat will likely just lead to burnt onions on the exterior before they can properly caramelize. This isn’t a quick process, but it’s worth the wait!
- Add a splash of water and watch for water evaporation to prevent burning. A dry pan will make the onions burn instead of caramelize!
How to store caramlized onions
Once cooled, the onions can be refrigerated in an airtight container for 4-5 days.
You can also freeze them for longer storage. Be sure to cool completely, then transfer to a freezer-safe zip-top bag or container. Squeeze out any excess air and freeze for up to 3 months. Thaw overnight in the fridge before using.
How to use caramelized onions
- Use them For Burgers & Sandwiches Topping: Pile them high on burgers like our Spinach and Feta Cheese Turkey Burgers, grilled chicken sandwiches, Philly cheesesteaks, or this Caramelized Onion Grilled Cheese recipe.
- On Flatbreads & Pizza: Spread them as a base for flatbreads or pizza before adding other toppings.
- In Eggs & On Toast: Mix into scrambled eggs or omelets, spoon over avocado toast.
- With Pasta: Toss with pasta recipes like our French Onion Pasta, gnocchi or ravioli.
- In Soups & Dips: Add to French onion soup, blend into caramelized onion dip.
- With Grilled Proteins: Spoon over grilled steak, Balsamic and Pesto Grilled Chicken, pork or fish as a flavor boost.
Frequently asked questions
Plan for at least 45 minutes to an hour of cooking time to fully caramelize onions. The process cannot be rushed or the onions are likely to burn on the outside before caramelizing through. Thinly sliced onions may caramelize a bit quicker in the 30-45 minute range, but thick slices can take over an hour. The key is going slowly over low heat.
There are a few potential reasons for burned or overly crispy caramelized onions:
–The heat is too high – keep it at low or medium-low and stir frequently
-You’re not deglazing the pan with liquid to prevent sticking and burning
-The onions are sliced too thick – thinner 1/4-inch slices caramelize faster
-You’re letting the onions cook for too long after caramelizing
Yes, you can make them in the oven, though it takes even longer – at least 1 hour. Toss sliced onions with oil and salt, spread on a baking sheet, and roast at 400°F, stirring occasionally, until deeply browned and caramelized, about 1 to 1 1/2 hours.
No, you don’t need to add sugar, as the slow cooking will naturally allow the onions’ sugars to concentrate and caramelize on their own with patience. However, adding just a pinch of sugar can help kickstart and accelerate the caramelization process slightly.
More Homemade and How To Recipes
- Homemade Tartar Sauce Recipe
- Homemade Pesto Recipe
- How to Make Homemade BBQ Sauce
- How to Make Homemade Nutella
- Homemade Healthy Alfredo Sauce
- How to make Homemade Buffalo Sauce
- How to make Homemade Ranch Dressing
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How to Caramelize Onions
Ingredients
- 6 medium yellow onions, halved and julienned thin
- 3 tablespoons extra-virgin olive oil
- ½ teaspoon sea salt
Instructions
- In a large cast iron skillet, add the olive oil and the julienned onions. Saute the onions over medium heat for 5 – 6 minutes or until they start to soften.
- Next, sprinkle the salt over the onions and stir. Reduce the heat to medium-low and let it cook slowly for 20 minutes. then lower the heat to low and let it sauté for another 30 minutes. The key is to not rush it.
- Stir the onions every 2-3 minutes until the onions start to become soft and golden brown or caramelized.
- The time it takes for them to caramelize will depend on the thickness of the onion and the amount of heat used.
Notes
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- Time: If the onions are thinly sliced, it may take less time for them to caramelize. it depends on the thickness of the sliced onions.
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- If you prefer the caramelized onion to have a deeper brown color, at the end, higher the heat and stir for a few more minutes until you get the color you need
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
