Upgrade your mashed potatoes with this mouth watering Caramelized Onion Mashed Potatoes recipe. With 16 heaping servings, this easy-to-make dish is perfect for a crowd!
Easy and delicious mashed potato with onion
No matter the occasion, it's always a good excuse to enjoy some mashed potatoes. Especially when they taste this good!
These caramelized onion mashed potatoes serve as the absolute best side dish of all time. There — I said it! Between the creamy potatoes and the rich and mouthwatering caramelized onion, every bite is better than the last.
I love to serve this potato recipe to a crowd, because it makes 16 servings! It's the perfect pot luck dish, and it makes a wonderful side no matter the main course.
Ingredients in caramelized onion mashed potatoes
This potato dish is filled with nutrients like potassium, fiber, vitamin B6, and even protein! Below are all of the ingredients that are used for both the onion and potato portions of the dish.
Onions
- Onions: Start with 2 lbs of yellow onions. Yellow onions tend to work the best when caramelizing, but if you have a different type, that's ok!
- Butter: Next, use ¼ cup of butter. Any brand is fine, but go with salted.
- Olive oil: 2 tablespoon of olive oil will help cook the onions to caramel perfection.
- Sugar: A dash of sugar makes all of the difference! Use 2 tsp.
- Salt & pepper: Finish off the onions with 1 teaspoon of salt and ½ teaspoon of pepper.
Potatoes
- Potatoes: Next up are the potatoes! Use 3.5 lbs of russet potatoes. They should be peeled and cubed before boiling.
- Butter: ¼ cup of butter will make these mashed potatoes nice and creamy. Cut the butter into cubes before using.
- Sour cream: The real secret to getting perfect mashed potatoes is sour cream! Use 8 oz.
- Milk: Then, fluff up the potatoes by adding ½ cup of milk. I prefer whole here, but skim or 2% will work too.
- Salt & pepper: Last but not least, include 1 teaspoon of salt and ½ teaspoon of pepper for a delicious flavor!
Kitchen tools used to make this mashed potatoes and onions recipe
You'll need a variety of kitchen tools to make this dish. Before you begin, gather the following:
- Cutting board
- Cutting knife
- Large skillet
- Spatula
- Large pot or saucepan
- Strainer
- Potato masher or ricer
To measure out the ingredients, you will need ½ tsp, 1 tsp, 1 tbsp, ¼ cup, and ½ cup sized measuring cups.
How to make these caramelized onion mashed potatoes
Ready to get started? This savory potato dish comes together in around one hour of total time. And trust me: Every minute is more than worth it!
First, prep and chop the onions into thin slices. I did half moons.
Next, heat a large skillet over medium heat and add the butter and olive oil. Once melted, add the sliced onions and cook for 15 minutes, stirring every 5 minutes.
Add the sugar, salt, and pepper. The onions will take an additional 20-30 minutes to caramelize and get brown. Be sure to stir occasionally. Once the onions have caramelized, turn off the heat and set aside.
While the onions are cooking, bring a large pot of water to a boil. Once boiling, add the potato cubes. Bring back to a boil and cook for about 12 minutes or until fork tender. Drain.
Then, add the drained potatoes back to the large pot and use a potato masher or potato ricer to mash. Add the butter, sour cream, and milk, and continue to mash until nice and smooth. Mix in the salt and pepper.
Pour the onions and all of the buttery juice into the potatoes and stir until well combined. Taste and adjust salt and pepper if needed. Enjoy!
Wondering about garnishes?
You can serve up your potatoes however you'd like! But if you want to get extra fancy, prepare them potato bar style and let everyone choose their own garnishes! Ideas include:
- Green onions
- Bacon
- Sour cream
- Shredded cheese
- Herbs
- Extra butter
Recipe Tips
How do restaurants make their mashed potatoes so good?
The secret is truly the sour cream! Adding sour cream to mashed potatoes makes them extra thick and creamy, and it creates an even richer flavor.
Is it better to caramelize onions in butter or oil?
In this recipe, we use both! The butter contributes to the flavor and the oil helps the onions caramelize perfectly.
What can I add to these onion mashed potatoes?
The options are endless! Enjoy these potatoes as-is or load them up with toppings like green onions, bacon, sour cream, shredded cheese, herbs, and/or extra butter!
If you liked this recipe, you'll want to try these!
Looking for some more delicious potato options? Here are some ideas for you to try! And as always, you can view all of our potato recipes here.
- Glazed Sweet Potatoes
- Healthier Sweet Potato Casserole
- Lightened Scalloped Potatoes
- Potato Sweet Corn Chowder
All recipes by Erin Morrissey and Photos by Sierra Inn
Caramelized Onion Mashed Potatoes
Ingredients
Method
- Prep and chop all onions into thin slices. I did half moons.
- Heat a large skillet over medium heat and add butter and olive oil. Once melted, add in sliced onions and cook for 15 minutes, stirring every 5 minutes.
- After 15 minutes, add sugar, salt, and pepper. Onions will take about an additional 20-30 minutes to caramelize and get brown. Be sure to stir occasionally. Once onions have caramelized, turn off heat and set aside.
- While onions are cooking, bring a large pot of water to a boil. Once boiling add in potato cubes. Bring back to a boil and cook for about 12 minutes or until fork tender. Drain.
- Add drained potatoes back to the large pot and use a potato masher or potato ricer to mash. Add in butter, sour cream, and milk and continue to mash until nice and smooth. Mix in salt and pepper.
- Pour onions and all of the buttery juice into the potatoes and stir until well combined. Taste and adjust salt and pepper if needed.
- Enjoy!
Patti says
Ideas for making this ahead? Could I make them Thanksgiving morning and keep them warm in a crockpot?
Erin says
Hi Patti, definitely! That would be a fabulous idea! Let me know how yours come out!
Tricia Sparks says
Absolutely delicious!! Regular mashed potatoes but up a notch! Everyone loved them at Friendsgiving and can’t wait to make them again for Thanksgiving. Very easy to make as well!
Erin says
Hi Tricia, so happy they were a hit!! 🙂
Ciara says
Erin, these are perfection. How did Mashed Pots survive without carmy onions for so long. These are so flavorful. No gravy needed. These need to be on all Turkey day tables.
Erin says
Hi Ciara, so happy you loved them so much!! 🙂
Corrin says
My husband made these for dinner tonight. I said, “just follow the recipe. You’ll be fine.” He did great! They taste amazing! Smooth & delicious onion flavor. He said, “super easy recipe & it tastes great!” Give this a try to mix up your potatoes!
Erin says
Hi Corrin, so happy you both loved them!! 🙂