Here is a recipe that combines two of my favorite things: Sour cream and onion flavor + mashed potatoes. The end result, Sour Cream and Onion Potato Bake, is just heavenly.
Growing up in the south, I’ve been taught to put things in a casserole dish and serve it so that it is hot and bubbly. Especially when the fall/winter weather rolls around and you’re attending gatherings for Thanksgiving, Christmas, and the holiday season. Here is a great one to make ahead and just pop in the oven at whatever party you are going to. [Just do steps 1-9 and finish in the oven when you get there]. It takes everyone’s favorite side dish (mashed potatoes) and amps them up with a fantastic and fun flavor of sour cream and onion.
Even though this Sour Cream and Onion Potato Bake are a show stopper, they aren’t *so crazy* in flavor that you can’t serve them on your holiday table. They won’t overpower your other dishes and instead, they’ll just surprise everyone and get them excited about the new spin on potatoes this year.
If you love this recipe, try these other potato recipes: Herbed Hassleback Potatoes, Whole30 Scalloped Potatoes, Greek-Style Potatoes.
Sour Cream and Onion Potato Bake

Ingredients
- 3 lb russet potatoes, peeled and cut
- 1 tbsp + 2 tsp kosher salt
- 4 tbsp salted butter
- 2 cups yellow onion, thinly sliced (or one medium onion)
- 3 cloves garlic, minced
- 2 tsp white vinegar
- 1 cup low-fat sour cream
- 1/4 cup low-sodium chicken broth
- 1/2 tsp freshly cracked pepper
- 1/2 cup freshly chopped chives (reserve 1/4 for topping)
- 1/2 cup mild cheddar cheese
Instructions
- Preheat oven to 375 degrees.
- Place cut potatoes into a large pot and fill with water so that it is just covering potatoes by 2 inches. Bring to a boil.
- Once boiling, add 1 tbsp of the salt and continue to boil until potatoes are fork-tender, about 10 minutes.
- Meanwhile, heat a large skillet over medium heat with 2 tbsp of the butter. Add onion and garlic then cook, stirring, until the onions are tender, 4 to 6 minutes.
- When potatoes are tender, strain and let steam escape a the colander for about 5 minutes, allowing excess water to drain [this prevents the potatoes from not tasting watery].
- Place potatoes in a large bowl and add the sour cream, white vinegar, chicken broth, pepper, 1/4 cup of the chives, and 2 tbsp of butter.
- Using a potato masher, mash until potatoes are your desired consistency. [For this recipe, I prefer mine a little lumpy.]
- Once mashed, stir in the onion mixture with black pepper and 2 tsp of kosher salt.
- Add the potatoes into an oven-safe dish and sprinkle with cheese.
- Place into the oven, uncovered until cheese is lightly browned, 10 to 15 minutes.
- Once browned, top with remaining chives, serve and enjoy!
34 Comments
Jesse
November 22, 2022 at 4:49 pmAnyone try making these in a crockpot?
Jess P
December 26, 2021 at 3:22 amMade these potatoes as a side dish for our Christmas dinner and my husband & I cannot stop obsessing over how delicious they were!!!! Definitely will be making this recipe for every holiday/special occasion going forward!!
Kristin
December 26, 2020 at 2:45 pmThese are amazing! Everyone should make these! I wouldn’t change a thing. A+ Recipe!
Cheryl
November 20, 2021 at 12:06 amThis was just so delicious! I had some triple cream Brie cheese which I sliced thinly on top of the potato along with some grated Parmesan. Mmhmmmh. So glad I found your recipe site! Thanks.
Cindy Whitehead
December 10, 2020 at 1:31 pmThis is my family’s favorite mashed potato recipe! Can it be made ahead of time and frozen?
Alex
December 10, 2020 at 10:57 pmI haven’t ever tried freezing them!
Heather
November 27, 2020 at 1:42 amwow these are so good! We made them for thanksgiving along side the brisket from your cookbook! It was delicious! I pureed the sauteed onions for the mashed potatoes which sounds weird but my husband would not have liked seeing the pieces of onions mixed in. I didn’t want to miss out on the flavor so I put them in the food processor with a little extra broth and they mixed in great! This might be my new go to mashed potatoes!
Alex
November 27, 2020 at 2:13 pmsuch a smart idea!!! So glad you loved it.
Molly
November 26, 2020 at 9:33 pmBest potatoes Ive ever had! You MUST make these!
Sarah
November 25, 2020 at 11:33 pmCan you substitute white wine vinegar or lemon juice for the white vinegar? Don’t have any on hand unfortunately.
Alex
November 27, 2020 at 2:15 pmsure! That should be just fine. I’d opt for White Wine Vinegar first.
Amy
November 24, 2020 at 11:51 pmHi! If I have to bake at 350 how long would you recommend? Until the cheese looks good on top?
Alex
November 25, 2020 at 4:18 pmit should be close to same time, around 20 mins.
MARIA
November 22, 2020 at 12:13 amWOW! Alex, I love all of your recipes and this one did not disappoint. I don’t think I will be able to eat mashed potatoes any other way now.
Alex
November 22, 2020 at 2:52 pmhaha, I am so glad.
Nicole B
November 21, 2020 at 8:13 pmHi Alex! What size baking dish do you recommend? Can’t wait to try for thanksgiving!
Alex
November 22, 2020 at 2:54 pm9x 13! enjoy!
Nicole B
November 25, 2020 at 12:52 amI made this a little early and had to sample. WOW! Another one knocked out of the park, you never steer us wrong! Thanks Alex, your work is very appreciated!
Sumanta Ray
November 21, 2020 at 3:00 pmAlex – this looks amazing and easy to add to the Thanksgiving table!! Thanks for sharing. 😊 What are your thoughts on subbing sour cream for plain Greek yogurt. Do you think it would turn out about the same?
Alex
November 21, 2020 at 3:20 pmI don’t think it will be the ‘same’ but I think it’d still be delicious!!
Jessica
November 20, 2020 at 10:22 pmWould these still taste good with gravy all over them? Might be a a loaded question cause what isn’t good with gravy all over it.
Chelsea
November 18, 2020 at 10:04 amOkay, this looks divine and I’ll definitely be making this for the “mashed potatoes” side this thanksgiving. I looked but didn’t see how many people this should serve?
Alex
November 19, 2020 at 2:23 pmIf you have a huge feast? this could easily serve 12. But if you don’t have as much, 8.
April
November 17, 2020 at 10:25 pmSounds amazing and can’t wait to make it for Thanksgiving! You mentioned it’s a good recipe to make ahead…could you tell us the steps?
Alex
November 18, 2020 at 12:08 amI would make it all (minus the baking part) and place it in a baking dish, cover and just keep refrigerated until ready to bake!
Marie
November 17, 2020 at 7:48 pmHi – could you make this 1 – 2 days before Thanksgivings? Wondering if I could have it ready to go then pop it in the oven before dinner time? Thank you!
Alex
November 18, 2020 at 12:09 amyes for sure!
Stephanie
November 25, 2020 at 12:03 amFor about how long/temp if you were reheating right before dinner?
Alex
November 25, 2020 at 4:17 pmId do close to 350, for about 20 mins.
Shannon Wehner
November 17, 2020 at 6:43 pmLooks amazing!! Do you recommend substitutions for making this dairy free? Or would it be better to pick a different recipe?
Alex
November 18, 2020 at 12:10 amI’d likely go for a different recipe; however, you could definitely use a DF Sour Cream, DF Shredded cheese, and Vegan butter.
Debbie
November 17, 2020 at 4:32 pmThis looks so good. When cooking for my vegetarian kids I’m wondering if you could recommend a substitute for the chicken broth. If it needs more liquid could you add milk or would you go with a veggie broth.
Thanks.
Alex
November 17, 2020 at 6:12 pmI would sub vegetable broth for the chicken broth. Enjoy!
Alex
November 18, 2020 at 12:10 amVeggie broth is totally fine!