Table of Contents
  1. Why I love this recipe.
  2. Everything you’ll need to make this recipe.
  3. Here’s how to make this recipe.
  4. These pro tips will make this recipe a success.
  5. Frequently asked questions about this recipe.
  6. You'll love these other Christmas side dish recipes.
  7. Watch how to make this recipe.
  8. Have I convinced you to make this recipe?
  9. French Onion Potato Casserole Recipe

Combining real potatoes with delicious caramelized onions is the ideal recipe for holiday happiness. Cream cheese, sour cream, whole milk, and an array of cheeses add additional smoothness to this already incredible dish. This straightforward French onion potato casserole comes together quickly and will become a side dish staple for your holidays!

Why I love this recipe.

I always looked forward to the potatoes we had for special occasions growing up. They were the ones we only had once in a while and instantly made the meal feel special. I realize now why mom made them. They were a casserole and could be prepared ahead and baked right before we sat down. This french onion potato bake is a version of the one I loved growing up but with the flavor turned up. Think about if your favorite French onion dip and mashed potatoes had a child; it would taste like these potatoes. These can be prepared ahead of time and refrigerated, then baked when needed. Quick, easy, make-ahead, and full of flavor, that is why this recipe works.

White baking dish filled with potato casserole with cheese melted on top sprinkled with parsley with serving on a Christmas plate with garland.

Everything you’ll need to make this recipe.

  • Russet potatoes are the pantry staple that works well for this recipe. Scrumb them well and leave the skins on.
  • Onion slowly cooks on the stove until it is condensed and caramelized. Choose yellow or white onions, as both contain the natural sugar needed.
  • Worcestershire sauce is a quick way to add a rich depth of flavor. The sauce adds a layer that gives everything else an added boost.
  • Cream cheese adds a creamy texture and helps hold the potatoes so they can be made ahead and baked later without losing any texture.
  • Parmesan cheese adds a nutty, salty flavor to enrich and season the casserole.
White marble surface filled with all ingredients needed to make French onion potato casserole including potatoes, sour cream, cream cheese, onions, cheese, and more.

Here’s how to make this recipe.

  1. Prepare the potatoes. Leaving the skin on, chop the potatoes into ½-inch pieces. Place into a large pot and cover in water. Add salt. Cover the pot and cook for 20 to 30 minutes.
  1. Prepare the onions. Melt the butter in a pan over medium heat. Thinly slice the onion and add to the pan. Add the salt and cook slowly for 30 to 35 minutes.
  1. Mash the potatoes. Using a potato masher, work the potatoes together until they’re mostly mashed. Add in the cream cheese, sour cream, warm whole milk, black pepper, Parmesan cheese, Monterrey jack cheese, and more salt.
  1. Assemble the dish. Using the masher, mix the ingredients with the potatoes until smooth. Take the onions off the heat once they’re caramelized. Add in Worcestershire sauce and chopped garlic. Mix together, then add the onions to the potatoes. Using a spatula, combine the onions and potatoes. Butter a 9×13 baking dish, then add the potatoes and spread them into an even layer. Sprinkle additional Monterrey Jack cheese on top.
  1. Bake the dish. Place into the preheated 350°F oven for 20 to 30 minutes or until the cheese is golden-brown. Garnish with chives, if desired. Serve warm.

These pro tips will make this recipe a success.

  • Cook the onions slowly. The key to well-caramelized onions is being patient. Excessive moisture needs to cook off the onions. Then, the sugars slowly get extracted. This means cooking the onions on low and letting them take their time.
  • Leave the skins on the potatoes when preparing them. Peeling potatoes can take a long time, and the skins add great texture and color to the dish.
Holiday plate with serving of French onion potato casserole with gold fork showing cheesy texture.

Frequently asked questions about this recipe.

Can this casserole be prepared and baked later?

Yes. The entire casserole can be cooked and poured into the casserole dish. Then cover and refrigerate for up to two days before serving. When ready to consume, remove from the refrigerator and bake. Remember that the casserole will be cold, so it will take longer to heat everything through, so allow for extra baking time.

Does the dish need to be baked a second time? Or will the hot potato mixture be good without the second bake?

Yes, the second bake is important. It is what allows the cheese that’s sprinkled on top to melt and create a delicious crust over the top. Additionally, the heat from the second bake distributes the added flavors, melding everything together.

What type of potato works best for this casserole?

Any potato that works well for mashed potatoes works perfectly in this recipe. You want to find a potato that is starchy, such as a russet or gold potato.

Bubbly cheese texture on top of French onion potato casserole with sprinkles of chopped parsley.

Watch how to make this recipe.

More Christmas side dishes

Have I convinced you to make this recipe?

I hope you make this recipe and put some food on your table. Leave a comment and share a star rating so you can let others know how much you love this recipe. This helps show others that this is a recipe they, too, can make, enjoy, and love!

Large white baking dish filled with French onion potato casserole with cheese over the top and sprinkled with chopped parsley.

French Onion Potato Casserole

5 from 8 votes
Combining real potatoes with delicious caramelized onions is the ideal recipe for holiday happiness. Cream cheese, sour cream, whole milk, and an array of cheeses add additional smoothness to this already incredible dish. This straightforward French onion potato casserole comes together quickly and will become a side dish staple for your holidays!
Prep Time 20 minutes
Cook Time 1 hour 5 minutes
Total Time 1 hour 25 minutes
Servings 12 servings

Ingredients

For the onions

  • 3 tbsp unsalted butter
  • 3 large onions sliced
  • ½ tsp kosher salt
  • 2 tsp Worcestershire sauce
  • 3 cloves garlic minced

For the potatoes

  • 3 lb russet potatoes
  • 8 oz cream cheese
  • 1 cup sour cream
  • ¾ cup whole milk warmed
  • 1 tsp black pepper
  • 1 ½ tsp kosher salt
  • ¾ cup Parmesan cheese
  • 2 cups shredded Monterey Jack cheese
  • chives

Instructions
 

For the onions

  • Melt the butter in a large skillet over medium heat. Once melted, add the sliced onions and kosher salt. Stir and sauté the onions. Adjust the heat down as needed so the onions do not burn or color but slowly cook. Continue to sauté the onions until they become dark and caramelize, 30-35 minutes.
    3 tbsp unsalted butter, ½ tsp kosher salt, 3 large onions
  • Remove from the heat and add the Worcestershire sauce and garlic. Stir and set aside.
    2 tsp Worcestershire sauce, 3 cloves garlic

For the potatoes

  • Preheat the oven to 350℉. Scrub the potatoes. Leave the skin on for a more rustic look, or peel if desired.
  • Dice the potatoes into ½-inch pieces and place them in a 6-quart stockpot. Cover the diced potatoes with water, add a pinch of kosher salt, and bring to a boil. Once boiling, reduce to a simmer, cover, and cook until the potatoes are fully tender, 20-30 minutes.
    3 lb russet potatoes
  • When the potatoes are tender, drain the water. Mash or mix the potatoes with a hand mixer until they are combined. Mix in the cream cheese, sour cream, and warm milk until the potatoes are smooth. Add the caramelized onions, black pepper, kosher salt, Parmesan cheese, and one cup of the Monterey Jack cheese.
    8 oz cream cheese, 1 cup sour cream, ¾ cup whole milk, 1 tsp black pepper, 1 ½ tsp kosher salt, ¾ cup Parmesan cheese, 2 cups shredded Monterey Jack cheese
  • Pour the potatoes into a butter 9×13 baking dish and sprinkle with the remaining one cup of Monterey Jack cheese. Cover with foil and bake for 30 minutes. Remove the foil and bake until the potatoes are warmed throughout and the cheese is beginning to brown, 20-30 minutes. Remove from the oven and top with chopped chives for a garnish.
    2 cups shredded Monterey Jack cheese, chives

Notes

Cook the onions slowly. The key to well-caramelized onions is being patient. Excessive moisture needs to cook off the onions. Then, the sugars slowly get extracted. This means cooking the onions on low and letting them take their time.
Leave the skins on the potatoes when preparing them. Peeling potatoes can take a long time, and the skins add great texture and color to the dish.

Nutrition

Serving: 1serving
Course Side Dish
Cuisine American
Difficulty Easy
Method Cooking

You May Also Like

Never miss a post by signing up for my newsletter.
Avatar for Kaleb

Kaleb

I’m Kaleb! I'm not a chef, professional baker, landscaper, or designer, but I like to play each on Knollgate Farm. Come join me on my journey and let's learn together!

Learn more about me

Leave a Comment

Recipe Rating:




This site uses Akismet to reduce spam. Learn how your comment data is processed.

10 Comments

  1. 5 stars
    Love it. Had to halve it due to using a conv toaster oven, so I’m sure will be making it again this upcoming week!

  2. 5 stars
    This French onion potato casserole is so good and so easy to make. I made it to go with our surf and turf dinner. Absolutely delicious!! I love your recipes and videos!

  3. Can I substitute gruyere cheese for the Monterey Jack cheese?
    Also in your twice baked potato casserole can I use gruyere cheese instead of cheddar cheese?
    Cant decided which recipe to make for Christmas dinner. Main protein will be glazed ham.

  4. 5 stars
    This was absolutely delicious and worth the time to let the onions slooowwly caramelize. I substituted Gruyere for Monterey Jack. It was the perfect side for beef tenderloin with au poivre sauce and roasted broccolini.

  5. 5 stars
    I made this side for our Christmas dinner. It was delish!! It’s loaded with flavor & so easy to make! It feeds many guests.
    Thank you so much Caleb for sharing this with us! Much appreciated.

  6. 5 stars
    I’ve made this recipe twice and it’s so delicious!! It serves quite a few guests.
    Thank you Kaleb!