French Onion Soup Casserole is the perfect combination of a classic soup and an easy casserole recipe. This delicious French Onion Casserole is filled with caramelized onions, crunchy baguettes, and plenty of cheese. It tastes just like the soup, but in an easy to make weeknight dinner! I love this easy French Onion Soup Casserole!
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Easy French Onion Soup Casserole
What do you get when you combine classic french onion soup with an easy casserole recipe? Easy French Onion Soup Casserole!
French Onion Soup is such a classic, and for good reason. The mixture of flavors is just perfect, and it always feels like such a special treat. I love the slightly sweet yet savory taste of the soup, with croutons and cheese on top. Yum!
Since I’m a fan of easy meals, of course I’m obsessed with casseroles. I wanted to take those amazing flavors from the soup and turn it into an easy casserole recipe that can be made any night of the week! This Easy French Onion Soup Casserole turned out so perfectly, and I think it’s even more crave-worthy than the soup.
You get the delicious caramelized onions, the crispy baguette slices, and lots of cheeeese all mixed together into one dish. I absolutely LOVE this French Onion Casserole!
This easy French Onion Casserole recipe is the perfect blend of flavors!
French Onion Casserole Recipe
What’s not to love about this recipe? An easy french onion soup recipe in the form of an easy to make casserole dish that the whole family will love! Easy, easy, easy (and SO tasty).
Take all of the ingredients and things you love about French Onion Soup, and put them in thus french onion casserole. You get the onions, the crunch, and the cheese! It’s easy to dig in and get the perfect bite with all the flavors melted together.
French Onion Soup Casserole Ingredients:
- Vidalia Onions
- Yellow Onions
- Baguette Slices
- Thyme
- Bay Leaf
- Beef Broth
- Chicken Broth
- Gruyere Cheese
- Dry Sherry
- Butter
- Salt & Pepper
How to Make French Onion Casserole
Gather up your ingredients and start making this amazing French Onion Casserole. You can make parts of this recipe ahead of time to help cut down on cook time. The onions can be made up to 3 days ahead, and the baguette slices can be made up to 5 days ahead. That way you can just jump in and bake the casserole when you get home from work and you’re ready to eat!
How to Make French Onion Soup Casserole:
- Bake the baguette slices in the oven at 400°F for 8-10 minutes.
- While the bread is toasting, add butter, sliced onions, salt & pepper, thyme and bay leaf into a prepared dutch oven. Remove toasted bread from the oven when it’s done.
- Place the lid on the dutch oven and cook the onions in the oven at 400°F. After 1 hour, stir the onions and then place them back in the oven, with the lid slightly ajar. Cook another hour.
- Now removed the onions from the oven and stir. They should be a dark brown. Cook another 30 minutes if they don’t seem dark enough. You really want to get a nice caramelized flavor out of them.
- Transfer the pot of onions to the stove top, and place over medium high heat. Remove the bay leaf.
- Add in the sherry, beef broth, and chicken broth. Bring the mixture to a boil, stirring constantly, for about 4-5 minutes until it has thickened.
- To make the casserole, layer half of the baguette slices into the casserole dish. Then spoon the onions over each bread slice, and top with the remaining slices. Sprinkle the cheese over everything.
- Cover the casserole dish with foil, and bake for 30 minutes at 400°F.
- After that, remove the foil, switch the oven to broil, and broil the casserole for about 3 minutes to make the cheese bubbly and golden brown.
Be sure to check the recipe card below for more detailed instructions and the full recipe.
Easy French Onion Recipes
French Onion Soup is good, but I’m a fan of french onion everything. This French Onion Casserole is a new favorite, but I’ve got plenty of other recipes with these amazing flavors! Try my One Pan French Onion Chicken Skillet for the perfect easy chicken recipe. Or make these Mini French Onion Dip Bread Bowl for a fun party appetizer.
I can’t wait for you to try this easy French Onion Soup Casserole because I just know you’ll love it! Make this French Onion Casserole for a delicious dinner and enjoy!
See the recipe card below for details on how to make French Onion Casserole. Enjoy!
If you like this recipe, try these other easy casserole recipes!
- Garlic Bread Pizza Casserole
- King Ranch Chicken Casserole
- Chicken Pot Pie Casserole
- Cheesy Chicken and Rice Casserole
- Beef Stroganoff Casserole
- Enchilada Stuffed Pepper Casserole
Easy French Onion Soup Casserole
Equipment
Ingredients
- 16 ounces baguette cut into ¼-inch slices (1 loaf)
- ¼ cup unsalted butter (½ stick)
- 2 Vidalia onions halved and cut top-to-bottom into ¼-inch-slices
- 3 yellow onions halved and cut top-to-bottom into ¼-inch-slices
- 1 teaspoon kosher salt
- ½ teaspoon freshly ground black pepper
- 5 fresh thyme sprigs leaves removed
- 1 bay leaf
- ½ cup dry sherry
- 1 cups unsalted beef broth
- 2 cups unsalted chicken broth
- 8 ounces freshly shredded Gruyere cheese (about 2 cups)
Instructions
- Preheat oven to 400°F and set the oven rack to the lower-middle position. Spray a 9×13-inch baking dish with nonstick cooking spray and set aside.
- Place the baguette slices on a metal rack placed inside a baking sheet and bake for 8-10 minutes or until golden brown. Remove from the oven and set aside until ready to use.16 ounces baguette
- While the bread slices toast, generously spray the inside of a large Dutch oven with nonstick cooking spray. Slice the onions (if they haven’t already been sliced).2 Vidalia onions, 3 yellow onions
- Add the butter, sliced onions, salt, black pepper, thyme leaves and bay leaf to the Dutch oven.¼ cup unsalted butter, 1 teaspoon kosher salt, ½ teaspoon freshly ground black pepper, 5 fresh thyme sprigs, 1 bay leaf
- Once the baguette slices have toasted, cover the Dutch oven tightly and cook the onions 1 hour. Remove pot from oven and stir, being sure to scrape the sides and bottom of pot.
- Return the pot to the oven with the lid slightly ajar and continue cooking another 1 hour.
- Once again, remove the pot from the oven and stir the onions (scraping the sides and bottom). The onions will be soft and a little darker than golden brown. If the onions need more color, return the pot to the oven (still with the lid slightly ajar) and cook another 30 minutes.
- Transfer the pot to the stovetop and turn the heat to medium-high. *Remember – the pot is HOT! Use oven mitts when touching the handles.*
- Remove and discard the bay leaf from the onions.
- Add sherry, beef broth and chicken broth; bring to a boil, stirring constantly, until slightly thickened, about 4-5 minutes.½ cup dry sherry, 1 cups unsalted beef broth, 2 cups unsalted chicken broth
- Layer half the toasted baguette slices in the prepared casserole dish.
- Spoon onion mixture evenly over the bread, and top the remaining bread slices.
- Sprinkle with shredded cheese and cover with foil.8 ounces freshly shredded Gruyere cheese
- Bake at 400°F for 30 minutes.
- Set the heat to broil and remove the foil.
- Broil 3 minutes or until cheese is bubbly. Watch closely.
- Garnish with additional thyme leaves, if desired.
Video
Becky’s Tips
- The baguette slices can be made up to 5 days ahead and kept in an airtight container until ready to use.
- The caramelized onions can be made up to 3 days ahead and kept refrigerated, in an airtight container, until ready to use.
Nutrition information is automatically calculated, so should only be used as an approximation.
Did you make this? Leave a comment!
Darn Jenny you forgot to bit*h about the time to cut the onions, grade the cheese, slice the bread………
Hi Jenny, we apologize for the confusion. We are in the process of updating many of our older recipes. The timing for this recipe reflected active cook time, not the total passive cook time. It has been updated!
I am sorry to hear it didn’t quite work out!
I made this today exactly according to recipe (except I used mozzarella on top because I didn’t have gruyere). It was absolutely delicious! The concept of French onion soup as a casserole is perfect and had me thinking, “I wish I’d thought of that!” My husband and I both loved it and I will definitely make it again! I prefer it as a side rather than a main dish, but I want to try it again with vegetable broth as a main dish for my vegetarian family members. I think it will adapt nicely for my vege family! Loved it!!!
Thanks for stopping by and sharing, Cari!
Don’t know who timed this recipie but some one needs to add up the time.
Haha I thought the same thing, I was searching for a quick version of a French onion casserole and thought I found a winner but adding up the minutes its 198 minutes. How is 3.3 HOURS anywhere close to the mentioned 50 minutes total?!
Super disappointed, too. Googled French Onion Casserole recipes and chose this one since it said 10 min prep time, + 40 minute cook time. Went to the grocery store, got everything I needed only to come home and find out it’s actually close to a 3-hour ordeal. Timing needs to be updated, super frustrating because I prepared my dinner around this recipe and now have to order in!
This is a great recipe! If my family had their way, I would make it every day
Yay! Thanks, Chelsea!
This sounds wonderful to me. My husband is touchy about things getting too soft in recipes and I am wondering if the bread gets “squishy” in any way from soaking up juices, or does it retain a firmness. He is just so darn sensitive about these things. For example, I don’t leave the bread to soak whan making french toast. A quick dip, and immediately onto the hot skillet. Any feedback would be very much appreciated.
So the bottom layer of bread does get soggy and soaks up all that soup. I totally understand bc my husband is the same way. You could keep that layer out and just do the top layer (it stays pretty crisp). You could then serve in bowls like a soup, topped with a top piece of bread. Hope you enjoy!
Becky, thank you so much for the reply and the great suggestion! I will give that a try.
Let me know how it goes!
I added some deepfried crispy onion strings to add some more crunchiness :) not a bad touch. Definitely didn’t need it, though, this recipe rocked.
Hi, what can I substitute for sherry, please? Thanks.
Hi! You can use chicken stock or cooking sherry. Enjoy!
This looks so cheesy & delicious! I bet it’s a hit with everyone! Can’t wait to try it!
This recipe is insanely good!
I’m so glad you love it!