Dinner · American

French Onion Chicken with Roasted Carrots and Mashed Potatoes

Daniel Brooks

Recipe by Daniel Brooks

Grilling & hearty mains · September 29, 2026

This is comfort food that eats like a restaurant plate but comes together on a busy weeknight. Juicy chicken gets crowned with jammy caramelized onions and melty mozzarella, served alongside creamy mashed potatoes and sweet roasted carrots. One skillet, one pot, one sheet pan, and dinner is done.

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French Onion Chicken with Roasted Carrots and Mashed Potatoes

Why you'll love this

  • All the flavor of French onion soup on a juicy chicken breast.
  • Comes together in about 45 minutes with everyday ingredients.
  • A full plate: protein, creamy potatoes, and roasted veg in one go.
  • Kid-friendly and cozy, but nice enough for company.

EveryDayMeal recipe

French Onion Chicken with Roasted Carrots and Mashed Potatoes

Prep
15m
Cook
30m
Total
45m
Serves
2
Level
Easy

Ingredients

  • 2 boneless skinless chicken breasts
  • 12 ounces carrots, peeled and sliced on a diagonal 1/4 inch thick
  • 5 medium russet or Yukon Gold potatoes, peeled and diced into 1/2-inch pieces
  • 1 large yellow onion, halved and thinly sliced
  • 1 packet beef stock concentrate (or 1/2 cup beef broth)
  • 1 1/2 cups shredded mozzarella
  • 2 tablespoons sour cream
  • 2 tablespoons butter
  • 1 teaspoon granulated sugar
  • 2 to 3 tablespoons vegetable oil
  • to taste salt
  • to taste black pepper

Equipment

  • Large skillet with lid
  • Medium pot
  • Baking sheet
  • Potato masher
  • Instant-read thermometer

Instructions

  1. Preheat your oven to 425 degrees F and wash and dry all the produce. Peel and slice the carrots on a diagonal into 1/4-inch pieces, dice the potatoes into 1/2-inch chunks, and thinly slice the onion so it caramelizes evenly.
  2. Spread the carrots on a baking sheet, drizzle with oil, and season with salt and pepper. Roast for 15 to 20 minutes until browned at the edges and fork-tender, tossing once halfway so they cook evenly.
  3. While the carrots roast, put the potatoes in a medium pot and cover with salted water by about 2 inches. Bring to a boil and cook 12 to 15 minutes until a fork slides in easily, then drain and return them to the pot with the lid on to keep warm.
  4. Heat a drizzle of oil in a large skillet over medium-high. Add the onion and cook 8 to 10 minutes, stirring now and then, until soft and golden. Sprinkle in 1 teaspoon sugar to boost the browning, then stir in the beef stock concentrate and 2 tablespoons water. Season with salt and pepper and cook 2 to 3 minutes more until thick and jammy. Scrape into a bowl and wipe out the pan.
  5. Pat the chicken dry with paper towels (dry meat browns better) and season all over with salt and pepper. Heat a drizzle of oil in the same skillet over medium-high, then cook the chicken 5 to 6 minutes per side until deeply golden and cooked through to 165 degrees F. In the last minute or two, pile the caramelized onions and mozzarella on top and cover the pan until the cheese melts.
  6. Set the pot of drained potatoes over low heat and mash with the sour cream, 2 tablespoons butter, salt, pepper, and a splash of water or milk until smooth and creamy. Divide the chicken, carrots, and potatoes between plates and serve hot.

Tips from the kitchen

  • Pound the chicken to an even thickness before cooking so it browns evenly and doesn't dry out on the thin end.
  • No lid for your skillet? Cover it with a baking sheet to trap the heat and melt the cheese fast.
  • A pinch of sugar on the onions is the secret to real caramelization, so don't skip it.

Estimated nutrition per serving: 720 cal · 52g protein · 58g carbs · 30g fat

Make it your own

  • Swap mozzarella for Gruyere or provolone for a sharper, more classic French onion flavor.
  • Use chicken thighs instead of breasts for extra juicy, hard-to-overcook meat.
  • No beef stock? Use 1/2 cup beef broth simmered down, or substitute a splash of Worcestershire for depth.

Storing & make-ahead

Store components separately in airtight containers in the fridge for up to 3 days. Reheat the chicken and potatoes gently in the microwave or a low oven with a splash of water to keep them from drying out. The carrots crisp back up nicely in a hot skillet.

Good to know

How do I know the chicken is done?
The safest way is an instant-read thermometer: 165 degrees F at the thickest part. The juices should run clear and the meat should feel firm, not squishy.
Can I make the mashed potatoes ahead?
Yes. Mash them up to a day ahead and reheat over low heat with a splash of milk or water, stirring until smooth and creamy again.
What if I don't have beef stock concentrate?
Use about 1/2 cup beef broth and simmer the onions a little longer to reduce and thicken it into that jammy sauce.
Can I double this for four people?
Absolutely. Double all the ingredients, use 2 teaspoons sugar and 1/4 cup water for the onions, and cook the chicken in batches so the pan doesn't crowd.

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