Triple Onion Mashed Potatoes
Deeply caramelized onions, crispy onion straws, and chives make up the three types of onion in this triple onion mashed potatoes! I was inspired by one of my favorite onion dips to make a mashed potato dish! It is so loaded with caramelized onions that it turns the whole thing brown! The caramelized onions bring such a deep and sweet flavor to these potatoes that they are completely transformed into something new! The crispy onions on top add much needed texture, and the chives bring a freshness to the dish! I love the juxtaposition of deeply caramelized onions and fresh chives. It’s like if a baby onion and an elderly onion were holding hands. Yes I know I am weird.
The inspiration for this recipe
For some reason the idea to do an oniony mashed potato came to me in like April. I have been sitting on it until November because I thought it would be perfect for Thanksgiving and the whole Holiday Season. As you can imagine I was very excited to finally make it.
I slow cooked onions to a perfect deep caramelized brown and mixed them in with cooked potatoes and lots of butter. Baking the whole thing with crispy onions and then topping with fresh chives before serving gives a nice to balance the cooked onion with a bit of raw. I am obsessed with how this came out! It’s nice to find a new place for crispy onion straws at the table since green bean casserole is garbage. I said it.
Caramelize the onions first
Dice the onions and put them in a pan with butter and just let them cook for a while. Dicing the onions makes them quicker to caramelize vs sliced. I like to stir them often and turn the heat up and down as needed to not burn but slowly reduce and build flavor.

Mixing the onions with the cooked potato
I baked the potatoes and then used a potato ricer to break them up. This helps concentrate the potato flavor that may have gotten a bit lost if you boiled them and then mixed them with the strongly flavored onions. Now we can add more flavorful liquids without the whole thing getting soupy or fully losing the potato flavor.

Baking the triple onion mashed potatoes
You can store the potatoes with the onions in the fridge until it’s time to eat. Then put them in a baking dish. Bake until warm, then top with the crispy onions. Bake a little more until the onions are brown.

I went with store bought for this one cause I had some on hand, but feel free to make your own!

Bake it some more, then finally add the chives before serving. So good!

The most deeply flavored mashed potatoes you can make!
Tips for success making the triple onion mashed potatoes
As I mentioned you could make the potato and onion mixture head and then warm it in the oven when it’s dinner time. Keep a good eye on the onions when cooking them, and make sure they are uniformly cut so they cook evenly. If the potatoes feel dry before you bake them, make sure to add more milk or water. They will dry further in the oven so they need to be soft going in! If you want to make your own onion straws, here is a great recipe.
Triple Onion Mashed Potatoes
Equipment
Ingredients
- 4 large russet potatoes
- 2 tablespoons butter
- 2 large yellow onions halved and sliced thin
- 1 stick butter cut into cubes and room temp
- 1/2 cup heavy cream
- salt and pepper
- 1 cup onion straws
- 1/4 cup chopped chives
Instructions
- Preheat oven to 350. Stab the potatoes a few times with a fork and put them on a baking sheet. Toss with oil and salt. Roast for about an hour and a half, flipping once in the middle of cooking, until tender.
- Right after you put the potatoes in, bring the 2 tablespoons of butter to medium heat in a large frying pan. Add the onions and cook about an hour slowly until deep brown. Stir and adjust the heat often.
- When the potatoes are done, allow to cool for 10 minutes, then slice them in half and scoop out the insides. Add the insides to a potato ricer or food mill. Process the potatoes into a bowl. Add the room temp stick of butter, the cream, and all the caramelized onions. Stir to combine. Add in half the chives. Season with salt and pepper. Stir once more. It might still seem a little clumpy but that is OK
- The dish can rest at this point for a few days in the fridge if desired.
- When ready to cook, add the potato mixture to a baking dish and cook at 350 for about 20 minutes if immediately, or 35 if from the fridge.
- Stir the potatoes, they will have smoothed out a bit. Top with the crispy onion straws and bake an additional 15 minutes until they are brown and ready.
- Remove from the oven and add the remaining chives. Serve.
I’m a massive fan of potatoes. I love this recipe and have made it multiple times. Absolutely delicious!! Thank you. 🙂
Wow thanks!