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Caramelized onion mashed potatoes.

Caramelized Onion Mashed Potatoes

Delicious way to enhance the flavor of mashed potatoes.
Course Side Dish
Cuisine American
Keyword caramelized onion mashed potatoes
Prep Time 10 minutes
Cook Time 45 minutes
Total Time 55 minutes
Servings 4 servings
Calories 341kcal
Author Joe Boyle


  • 2 lbs russet or yukon gold potatoes
  • 2 large yellow onions
  • 2 tbsp butter
  • 1 tbsp olive oil
  • kosher salt


  • Dice the onions or slice thinly. Add the butter and olive oil to a large skillet over medium heat. Once the butter is melted, add the onions and a couple pinches of salt. Cook on medium heat until the onions start to become opaque, 4 to 6 minutes.
  • Lower the heat to low so that the oil gently boils around the onions. Stir occasionally. The onions will slowly begin to turn a light brown color. If they begin to char, lower the heat. Once the caramelization starts, stir more frequently until the onions are a medium brown color, 30 to 45 minutes. Remove from the heat and keep warm.
  • While the onions are cooking, peel and cut the potatoes into approximately 1 inch pieces. Place in a saucepan and add water to 1 inch above the potatoes. Place on the stove on high. Once boiling, cook for 12 to 15 minutes until fork tender. Drain and reserve 1 cup of the water.
  • Mash the potatoes using the reserved water until creamy. Add the onions and blend in until fully incorporated. Taste and add salt as desired. Serve hot.


The caramelized onions can be made a day or two ahead, refrigerated, and then reheated.
I used the potato water to reduce the calories of the potatoes. You may use butter, whole milk, or half and half but the calories will be higher. The nutrition information is based on using only the water.


Calories: 341kcal