Easy to make and impressive, this French Onion Chicken is packed with savory flavor. It’s naturally gluten-free and perfect paired with simple vegetable sides. Enjoy it with my mashed potatoes and roasted asparagus. It’s also a great recipe for entertaining or at-home date nights. You’ll also find some tips in the recipe for how to prep the onions ahead of time to save on cooking time.
I got my love of French Onion Soup from my mom, and what’s not to love?! Deeply caramelized onions in a flavorful broth topped with toasty bread and cheese is always welcome.
Watch How To Make French Onion Chicken
Instead of a gluten free version of the classic, I wanted to turn the same flavors into a one pan dinner. I replaced the bread with chicken, only to find out so many other people have been doing this for a very long time.
So while this recipe isn’t anything new, I sure hope you enjoy my version of this dish. My recipe is inspired by classic French Onion Soup from Cook’s Illustrated where they add thyme and balsamic vinegar for depth of flavor in the broth.
I also like to add 2 kinds of cheese because I find both Gruyere and Swiss together add more flavor. Swiss cheese is subtle and Gruyere alone can be overwhelming. But the 2 together are the perfect combination to top this dish.
Ingredients & Substitutions
- Chicken breasts – boneless skinless chicken breasts weighing about 8 ounces each work really well in this recipe. You can also use boneless skinless chicken thighs. They will take up more space so you might need to transfer the onions to a baking dish to allow the chicken thighs space.
- Flour – for thickening the sauce, you can use gluten free flour, Einkorn wheat, or all-purpose flour. I like to use Bob’s Red Mill 1:1 gluten free flour.
- Onions – both white onions and yellow onions work in this recipe. Any sweet onion, like Vidalia onions, also works. Just avoid red onions because caramelizing them gives the dish a strange color.
- Onion granules – is also sometimes called onion powder, but you can see in the above photo onion granules have a granular texture. I find that onion granules give a nice toasty onion flavor that adds nice depth to the caramelized onions.
- Garlic – a small amount of garlic adds depth of flavor, but I like to keep it subtle for the full onion flavor to shine through.
- Broth & white wine – make up the broth part of this French Onion Chicken. It’s very important that the white wine you choose is a dry white wine like a Sauvignon Blanc or Pinot Grigio. Don’t use a sweet wine like Moscato etc because the sugar will overwhelm this dish. You can also use just broth, but white wine adds the depth of flavor you come to expect from the classic recipe.
- Balsamic vinegar – I use aged balsamic vinegar, but any qualtiy balsamic or balsamic reduction works here.
- Thyme – is the classic herb in French Onion Soup. Fresh thyme really is worth it in this recipe, but dried thyme will also work when needed.
- Cheese – as mentioned, I like to use 2 cheeses for this dish. Both Swiss and Gruyere are classic choices. Swiss is very subtle and Gruyere has a much stronger flavor. The 2 together are the perfect combo. However to keep it simple you can choose just one cheese. If you go with Gruyere cheese just be judicious in how much you add so the flavor isn’t overwhelming. Provolone cheese also works, but again it has a very subtle flavor.
How to make this recipe step by step
Step 1: Start by cutting both ends off the onions and cutting them in half from the top to the bottom. Lay each half flat side down and cut across the rounded tops to create 1/4″ thick half-moon slices.
Step 2: Next sear the chicken breasts over medium-high heat. Remove the browned chicken breasts from the pan and set them aside.
Step 3: Next add the sliced onions along with the remaining butter and cook over low to medium-low heat stirring as needed to prevent sticking.
Step 4: After 30-40 minutes, your onions will be perfectly caramelized.
I know this may seem like a lot of time, but there is no shortcut to caramelized onion and the time is what brings the incredible flavor. See my tips below for how to make them ahead of time.
Step 5: When the onions are done, add the thyme and flour. Stir to combine the flour and make sure there are no lumps before adding the white wine and beef broth, stirring as you add the liquid.
Season the onion mixture with sea salt and pepper. Then top the onions with the browned chicken breasts.
Step 6: Top the chicken breasts with the grated/shredded gruyere. Place the Swiss cheese on top of the chicken. Bake in the oven to melt the cheese and it’s bubbling, and the chicken is done in the center, 165ºF.
Garnish with a sprinkle of chopped parsley for a bright pop of color and serve.
Ways to serve this
- Try this with my Best Mashed Potatoes and Sautéed Green Beans. My Garlic Roasted Carrots, Roasted Broccoli, Roasted Brussels Sprouts, and Perfect Roasted Asparagus all work here too.
- For a lighter option, try this dish with my Creamy Mashed Cauliflower and Sautéed Spinach.
- Add a fresh veggie with my Apple Spinach Salad or Strawberry Spinach Salad.
FAQ’s
The best way to ensure juicy chicken is to use an instant-read thermometer. Chicken breasts are done when they register 165ºF at the thickest point. When chicken is overcooked it will become dry. And chicken breasts which are very lean will be even drier if overcooked.
Yes, you can use any melting cheese you like here. Try to pick something with more flavor than mozzarella cheese. Gruyere and/or Swiss cheese are classic pairings with these flavors, but harvarti works it’s just different.
Storing leftovers
- To store – place any leftovers into an airtight container and refrigerate for up to 4 days.
- Make ahead – you can cook the caramelized onions ahead of time and store them in the fridge for up to 4 days ahead of time. With the onions cooked, it’s really easy to put this dish together.
- Reheating – slice up the chicken breasts and add it to the pan along with the onion mixture and heat covered over medium heat adding water as necessary to keep it from sticking until it’s heated through. Or you can also reheat in the microwave.
- To freeze – this dish freezes ok, although the cheese changes in texture a bit when it’s thawed. Freeze any leftovers in an airtight container for up to 3 months. Defrost in the refrigerator overnight before reheating.
Tips & Tricks
- Try caramelizing the onions ahead of time to reduce the cooking time. You can keep them in the fridge up to 4 days and they freeze really well too.
- And since caramelized onions are so good, I usually make a double batch of these to freeze for another French Onion Chicken later. You can also dice up and caramelized a second pan of onions to use in my In and Out Burgers. I figure if you’re going to be around to ocassionally stir the onions for up to 40 minutes, you might as well make 2 pans!
Dietary Options & Substitutions
- Dairy-free & Paleo – you can make this with olive oil, (or use ghee if tolerated) and omit the cheese for a different but tasty version. Chicken with a caramelized onion sauce is still very good, or you can use your favorite dairy free cheese.
More Chicken Breast Recipe Inspiration
I really hope you enjoy this French Onion Chicken! If you do get a chance to make this recipe, I’d love to hear from you in the comments.
French Onion Chicken
INGREDIENTS
- 2 pounds boneless skinless chicken breasts - 4
- 4 tbsp salted butter - or ghee
- 2 large onions - 2 pounds, or 3 medium onions, white, yellow, or sweet onions
- 1 tsp onion granules - see notes
- 2 cloves garlic - minced
- 1 tsp fresh thyme leaves - stems removed
- 1 tbsp gluten-free flour - or all-purpose flour
- 1/2 cup dry white wine - not sweet, or additional broth
- 1 tbsp balsamic vinegar
- 1 cup low-sodium chicken broth - or beef broth
- 2 cups grated Gruyere cheese
- 4 slices Swiss cheese
- chopped fresh parsley & sprigs for garnish
INSTRUCTIONS
- Heat a large cast iron skillet (9-10") over medium-high heat. When the pan is hot but not smoking, add 1 tbsp of the butter and sauté the chicken breasts until browned on each side, about 3 minutes per side. Remove them from the pan and set aside.
- In the same skillet, add the remaining 3 tbsp of butter and the sliced onions. Lower the heat to medium-low and cook, stirring occasionally until the onions have softened and caramelized, about 30 minutes. Monitor the heat and lower it as needed so the onions cook slowly to caramelize to the center rather than brown the outside only.
- Halfway through cooking the onions, preheat the oven to 450ºF.
- When the onions are done, add the onion granules and garlic and cook for 1-2 minutes. Then add the thyme and flour. Stir to combine then add the dry white wine. Stir to deglaze the pan and add the balsamic vinegar and chicken stock.
- Bring to a simmer, then place the sautéed chicken breasts on top of the French onion 'gravy'. Then top each chicken breast evenly with the grated Gruyere cheese, then 1 slice of Swiss cheese over the top of the grated cheese.
- Bake until the chicken is done (an instant-read thermometer will read 165ºF) and the skillet is bubbling about 20 minutes.
- Remove from the oven, top with parsley for a garnish if desired, and serve.
Hi Kari – This was the first entree recipe of yours that we’ve tried and wow! Great flavors and you absolutely hit the mark of no-bread French onion soup with extra protein. We didn’t have the granules so replaced 1:1 with onion powder This will be in our regular rotation and is now added to the short list of recipes we’ll use when entertaining friends. Now we can’t wait to try some of your other great-looking recipes.
Thanks!
I’m so glad to hear you enjoyed it enough to make it regularly and I really hope you find some more new favorites as well! The onion powder definitely works, but if you ever do come across onion granules or granulated onion it has a slightly more ‘toasty’ flavor and I love using it instead of onion powder.