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A close up photo of caramelized onions in a cast iron skillet

Caramelized Onions in a Cast Iron Skillet

Caramelized onions aren't hard to make, but they do require patience. Making them in a cast iron skillet is ideal, as it heats evenly, and provides enough surface area to not overcrowd the onions (meaning they caramelize vs. steam). The final product is worth the wait though, producing sweet, jammy and delicious onions you can use in just about any way you can imagine.
Prep Time 15 minutes
Cook Time 45 minutes
Course Appetizer, Dinner, Side Dish, Soup
Cuisine French
Servings 2 cups
Calories 232 kcal

Equipment

  • Cast Iron Skillet

Ingredients
  

  • 6-8 onions medium sized
  • 2 tablespoon butter
  • water as needed

Instructions
 

  • Preheat your cast iron skillet over medium low heat. You can maybe go as high as medium if you keep a close eye on them, but no higher.
  • First, peel all of your onions. Cut each one in half, and then slice off the roots and tops. Thinly slice vertically from the root (see video).
  • Add the butter to the pan. After it melts add the onions by two handfuls at a time, letting each bunch cook for about a minute before you add the next onions. Repeat until all the onions are in the pan.
  • Stir the onions every 2-5 minutes, as needed.
  • Add water, as needed (see notes).
  • Once the onions are a deep, golden color, remove from heat. Store in an airtight container in the fridge for up to one week.

Video

Notes

Once your onions have finished sweating (releasing their moisture), the may be too dry and start burning to the bottom of the pan. If this happens, add 2 tablespoons of water and stir. It's just enough lubrication to keep them from burning. Repeat as needed throughout the process. 
Don't be tempted to turn up the heat to speed up the process. It doesn't work. The onions just burn. Trust me. 
WATCH THEM SO CAREFULLY! I cannot stress this enough. Caramelized onions are a labor of love, and they will burn if you turn your back on them. 

Nutrition

Serving: 2cupsCalories: 232kcalCarbohydrates: 31gProtein: 4gFat: 12gSaturated Fat: 7gPolyunsaturated Fat: 1gMonounsaturated Fat: 3gTrans Fat: 1gCholesterol: 30mgSodium: 113mgPotassium: 485mgFiber: 6gSugar: 14gVitamin A: 356IUVitamin C: 24mgCalcium: 79mgIron: 1mg
Keyword caramelized onion cast iron
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