Skip to content

Get 5 Secrets to Make Homemade Taste Food Better + New Recipes Weekly!

    Caramelized Onion Recipe

    Published June 27, 2024. This post may contain affiliate links. Please read my disclosure policy.

    This classic caramelized onion recipe is slow-cooked until dark brown, tender, and loaded with delicious sweet and savory flavors. Once you learn how to do this properly, you’ll never want a caramelized onion again.

    I often use this traditional process of preparing onions, as it greatly enhances the flavor of food. Try using it and serving it on my Smash Burger or with my Smothered Pork Chops.

    caramelized onions in a pan


     

    Caramelized Onions

    Caramelized onions are quickly or slowly cooked with varying degrees of darkness and sweetness to elevate the flavor. This is a classic technique that I often use to intensify and change the taste of the onion, which then compliments whatever I’m serving it with.

    These can be used as the main ingredient, like in a French Onion Soup, or on top of a sandwich. I believe a good caramelized onion takes time and should be very dark in color but not burnt. I’ve slightly changed how I caramelize onions by seasoning them with salt and cooking them over higher heat in the beginning to help the browning process before slowly cooking them over low heat. In the past, I would cook them unseasoned over low heat for 70 to 90 minutes. Both ways work and render excellent results.

    Ingredients and Substitutions

    caramelized onions ingredients
    • Onions — Yellow onions are best for caramelizing. However, I like to combine them with red onions. You can also use white or sweet onions or any combination of the four.
    • Vinegar – Apple cider vinegar is used for the onions. You can also use balsamic, white wine, or white distilled vinegar.
    • Butter – I always use unsalted butter in my cooking and baking to control the sodium content.
    • Salt – I always use coarse salt in my cooking and baking.

    How to Make Caramelized Onions

    Slice the onions about 1/8” to ¼” thick.

    slicing onions

    Add the butter to a large, thick-bottomed stainless-steel pan or pot or a large cast iron skillet and heat over medium heat. Once the butter is melted, add the onions, gently season with salt, maybe ¼ teaspoons, and mix to combine.

    cooking oninos

    Cover and let the onions stand untouched for 5 to 6 minutes. During this process, the onions will release moisture from the salt, helping steam them while covered, making the process go faster.

    lid on a pot

    Remove the lid, and you’ll notice the onion liquid will be evaporated. Stir the onions for 1 to 2 minutes. They should start to turn light brown.

    caramelizing onions

    Turn the heat to low-to-low medium and stir every 6 to 8 minutes for 30 to 35 minutes or until very dark brown.

    adding vinegar to onions

    Deglaze with the vinegar, season with salt, and stir to combine Serve the caramelized onions. Try adding them to my patty melt recipe.

    patty melt sandwich

    Make-Ahead and Storage

    Make-Ahead: You can make these caramelized onions 2 days ahead.

    How to Store: Cover and keep them in the refrigerator for 5 to 6 days. You can freeze these covered for up to 3 months. Thaw them in the refrigerator for 1 day or until thawed.

    How to Reheat: Add the onions to a large frying pan with 1tablespoon of oil or butter over low to medium heat and sauté for 3 to 4 minutes or until warm.

    Chef Billy Parisi

    Chef Notes + Tips

    • You can also use a non-stick skillet or enameled pan.
    • If you start to see the onions sticking too much to the bottom of the pan and overly browning on the verge of burning, deglaze with a few tablespoons of water. This will temporarily help slow down that process. Then, be sure to adjust the heat lower.
    • The darker the onions, without burning them. of course, the sweeter and more savory they become.

      More Onions Recipes

      Share this Post

      Let's Cook - Chef Billy Parisi

      Caramelized Onions Recipe

      This classic caramelized onion recipe is slow-cooked until dark brown, tender, and loaded with delicious sweet and savory flavors.
      Servings: 1 cup
      Prep Time: 5 minutes
      Cook Time: 45 minutes

      Ingredients 

      • 2 large yellow onions
      • 1 large red onion
      • 2 tablespoons unsalted butter
      • 2 teaspoons apple cider vinegar
      • coarse salt to taste

      Instructions

      • Slice the onions about 1/8” to ¼” thick.
      • Add the butter to a large thick-bottomed stainless-steel pan or pot, or a large cast iron skillet and heat over medium heat.
      • Once the butter is melted, add onions, gently season with salt, maybe ¼ teaspoon, and mix to combine.
      • Cover and let the onions stand untouched for 5 to 6 minutes. During this process, the onions will release moisture from the salt, helping steam them while covered, making the process go faster.
      • Remove the lid, and you’ll notice the onion liquid will be evaporated. Stir the onions for 1 to 2 minutes. They should start to turn light brown.
      • Turn the heat to low-to-low medium and stir every 6 to 8 minutes for the next 30 to 35 minutes or until very dark brown.
      • Deglaze with the vinegar, season with salt, and stir to combine.
      • Serve the caramelized onions. Try adding them to my patty melt recipe.

      Notes

      Make-Ahead: You can make these caramelized onions 2 days ahead.
      How to Store: Cover and keep them in the refrigerator for 5 to 6 days. You can freeze these covered for up to 3 months. Thaw them in the refrigerator for 1 day or until thawed.
      How to Reheat: Add the onions to a large frying pan with 1tablespoon of oil or butter over low to medium heat and sauté for 3 to 4 minutes or until warm.
      You can also use a non-stick skillet or enameled pan.
      If you start to see the onions sticking too much to the bottom of the pan and overly browning on the verge of burning, deglaze with a few tablespoons of water. This will temporarily help slow down that process. Then, be sure to adjust the heat lower.
      The darker the onions, without burning them. of course, the sweeter and more savory they become.

      Nutrition

      Calories: 335kcalCarbohydrates: 31gProtein: 4gFat: 23gSaturated Fat: 15gPolyunsaturated Fat: 1gMonounsaturated Fat: 6gTrans Fat: 1gCholesterol: 60mgSodium: 17mgPotassium: 496mgFiber: 6gSugar: 14gVitamin A: 706IUVitamin C: 24mgCalcium: 83mgIron: 1mg
      Course: accon, Side Dish
      Cuisine: French