How To Caramelize Onions

Caramelized onions on a plate with a fork.

Learn How To Caramelize Onions perfectly every time with this simple, step-by-step guide. Slow-cooked until golden, sweet, and jammy, they add rich flavor to burgers, bowls, sandwiches, and more.

Course Side Dish

Cuisine American

Keyword caramelized onions

Prep Time 5

Cook Time 1

Total Time 1 5

Servings -8 servings

Calories 86kcal

Author Tawnie Graham of Kroll's Korner

Ingredients

4-6 large yellow onions you can use more onions if you’d like for a larger batch, just add a little more olive oil to the pan
2 Tbsp. unsalted butter
1 Tbsp. olive oil
Kosher salt and black pepper
Water for deglazing

US Customary - Metric

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Instructions

Grab the correct pan: You’ll want a large stainless steel skillet (wide-heavy bottom) or a cast iron pan. Try NOT to use a nonstick.
Slice the onions: Cut the roots and tops off of the onions, then cut them in half, then slice “with the grain”, making julienne slices about 1/4-1/8-inch thick. Check out this post for reference on how to cut onions. 🤗
4-6 large yellow onions
Butter & oil: Heat a skillet over medium-high heat to start. Add the butter and oil and allow the butter to melt.
2 Tbsp. unsalted butter, 1 Tbsp. olive oil
Add the onions: Add in all the onions (it’s a lot, I know, but they will cook down!).
Cook on high to start: Cook for about 8-10 minutes until onions soften a bit. The onions will become soft and glossy but not browned in this step. Start Timer
Caramelization starts: Turn the heat to medium-low. Over the next 30 minutes, you’ll really begin to see the onions changing color. You’ll want to stir every 3 minutes or so. Start Timer
Fond: You’ll most likely begin to see brown bits on the bottom of your pan now. This is fond and it’s added flavor we want in the onions so just add a small splash of water and scrape it back into the onions. Add small amounts of water, you don’t want to flood the onions.
Water for deglazing
Last 10-15 minutes: This last bit of time is where the onions will start to become jammy, deep golden, and smell sweet! It’s important not to rush the process. The slow development of the sugars is important. *Note: this can take longer, sometimes up towards 90 minutes. Don't rush the process! 🤗 Start Timer
Finish: Season with salt and pepper and enjoy on burgers, grilled cheese, breakfast sandwiches, add to charcuterie boards, etc.
Kosher salt and black pepper

Video

Notes

Store: Let the onions cool completely, then store them in an airtight container in the fridge for up to 5 days.
Freeze: You can also freeze caramelized onions if you want to save some for later. Just portion them into small containers or silicone ice cube trays for easy grab-and-go servings. Freeze for up to 3 months. Thaw overnight in the fridge or gently reheat straight from frozen.
Reheating: Warm in a skillet over low heat or microwave in short intervals until heated through. If they seem dry, add a tiny splash of water or olive oil to loosen them up.
Some of my favorite recipes to add these caramelized onions to are my Cheeseburger Tacos, Homemade Burgers, Garlic Bread Pizza, Philly Cheesesteak Sliders, or Chipotle Chicken Quesadillas, but honestly, you really can't go wrong adding them to just about anything!😉

Nutrition