French Onion Chicken Sandwich

by / ⠀Main dishes Recipes Sandwiches / August 29, 2013

Everyone loves French onion soup but not everyone loves the extra fat sodium and calories that it packs. In this sandwich alternative, we added baked chicken to spinach and caramelized onions, and just a slice of ooey gooey Swiss cheese.


Serves: 4

Prep time: 10 minutes

Cook time: 25 minutes


  • 1 tablespoon extra virgin olive oil
  • 1 large white onion, thinly sliced
  • 1 teaspoon granulated sugar
  • Olive oil nonstick cooking spray
  • 2 boneless, skinless chicken breasts, halved crosswise and pounded to 1-inch thickness, if necessary
  • 4 slices Swiss cheese
  • 4 hamburger buns
  • 2 cups baby spinach


1. In large skillet, heat oil over medium heat. Add onion and sugar; cook 25 minutes or until onions are deeply caramelized, stirring frequently.

2. Meanwhile, preheat oven to 400 degrees F. Spray rimmed baking pan with nonstick spray. Place chicken on prepared pan. Bake until chicken loses its pink color throughout and internal temperature reaches 160 degrees F, about 16 minutes.

3. Turn oven to broiler function (high heat). Place cheese slices on chicken pieces. Broil 1 to 2 minutes or until cheese is melted and golden brown. Build sandwiches using hamburger buns, spinach, chicken and caramelized onions.

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  • Reply
    January 21, 2015 at 6:31 pm

    These were delicious. I put some BBQ sauce on the buns and it worked so well with everything but next time I think I’ll marinate the chicken in the sauce instead. The chicken was perfectly moist but just too plain for a sandwich. Served with some steak fries and a nice salad… perfect meal for more of a relaxed night. In the summer, grilling the chicken for these will be heaven!

  • Reply
    June 23, 2015 at 2:15 am

    We just made these for dinner and loved them. Admittedly, we made one alteration to the recipe. We marinated the chicken breasts in a little olive oil and a package of dried onion soup mix. We sealed the chicken, with about a tablespoon of olive oil and one package of onion soup mix into a zip lock bag (gave them a good squeeze to blend and coat all the chicken) for a couple hours before grilling them. To us, this step made the sandwich even more reminiscent of french onion soup – we actually cant imagine if we hadn’t done this step. We will definitely be making these again. Thanks for the recipe!

  • Reply
    July 10, 2015 at 6:02 pm

    I would’ve suggested in this recipe to season the chicken….. This is great but the chicken is going to be sooooo bland without proper seasonings

  • Reply
    David Summerbell
    June 8, 2016 at 3:04 pm

    I love this recipe and tried it and it came out ever better than I expected! My kids absolutely devoured it so thanks alot for sharing this recipe and your wonderful pics.

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