Dinner · American

French Onion Chicken with Roasted Carrots and Mashed Potatoes

Daniel Brooks

Recipe by Daniel Brooks

Grilling & hearty mains · July 29, 2026

This is the cozy French onion flavor you love, turned into a full dinner plate. Juicy chicken breasts get crowned with jammy caramelized onions and melty mozzarella, then served with roasted carrots and buttery mashed potatoes. It comes together in about 40 minutes, all on one sheet pan, one pot, and one skillet.

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French Onion Chicken with Roasted Carrots and Mashed Potatoes

Why you'll love this

  • All the rich French onion flavor in a complete, satisfying dinner plate.
  • Uses one skillet, one pot, and one sheet pan for easy cleanup.
  • Ready in about 40 minutes on a busy weeknight.
  • Caramelized onions and melty mozzarella make it feel like a restaurant meal.

EveryDayMeal recipe

French Onion Chicken with Roasted Carrots and Mashed Potatoes

Prep
15m
Cook
25m
Total
40m
Serves
2
Level
Medium

Ingredients

  • 2 boneless skinless chicken breasts
  • 12 ounces carrots
  • 5 medium russet or Yukon Gold potatoes
  • 1 large yellow onion
  • 1 packet beef stock concentrate (or 1/2 cup beef broth)
  • 1 1/2 cups shredded mozzarella
  • 2 tablespoons sour cream
  • 2 to 4 tablespoons butter
  • 1 teaspoon granulated sugar
  • 2 to 3 tablespoons vegetable oil
  • to taste salt
  • to taste black pepper

Equipment

  • Baking sheet
  • Medium pot
  • Large skillet with lid
  • Potato masher
  • Cutting board and chef's knife

Instructions

  1. Preheat your oven to 425 degrees F. Wash and dry the produce. Peel and cut the carrots on a diagonal into 1/4 inch thick pieces, dice the potatoes into 1/2 inch chunks, and halve, peel, and thinly slice the onion so it cooks down evenly.
  2. Toss the carrots on a baking sheet with a drizzle of oil, salt, and pepper, then spread them in a single layer. Roast for 15 to 20 minutes, until browned at the edges and tender when pierced, so they turn sweet and caramelized.
  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. Drain, return them to the pot, and cover to keep warm.
  4. Heat a drizzle of oil in a large skillet over medium-high. Add the onion and cook, stirring now and then, until softened and lightly browned, 8 to 10 minutes. Sprinkle in 1 teaspoon sugar, then stir in the stock concentrate and 2 tablespoons water. Season with salt and pepper and cook 2 to 3 minutes more, until jammy and glossy. Scrape into a bowl and wipe out the pan.
  5. Pat the chicken dry and season all over with salt and pepper. Heat a drizzle of oil in the same skillet over medium-high. Cook the chicken 5 to 6 minutes per side, until deeply browned and cooked through (165 degrees F inside). In the last 1 to 2 minutes, pile the caramelized onion and mozzarella on top and cover the pan until the cheese melts.
  6. Set the pot of drained potatoes over low heat. 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 mashed potatoes among plates and serve.

Tips from the kitchen

  • Pound the chicken breasts to an even thickness before cooking so they brown and finish at the same time without drying out.
  • No lid for your skillet? Cover it with a baking sheet to trap steam and melt the cheese fast.
  • Give the onions time to truly soften and brown before adding the sugar and stock, that slow color is where the deep flavor comes from.

Estimated nutrition per serving: 720 cal · 52g protein · 62g carbs · 30g fat

Make it your own

  • Swap mozzarella for Gruyere or provolone for a sharper, classic French onion taste.
  • Use boneless thighs instead of breasts for a juicier, more forgiving cook.
  • Stir a little roasted garlic into the mashed potatoes for extra depth.

Storing & make-ahead

Store leftovers in an airtight container in the fridge for up to 3 days. Reheat the chicken gently in a covered skillet or the microwave, and loosen the mashed potatoes with a splash of milk when warming so they turn creamy again.

Good to know

Can I make the caramelized onions ahead?
Yes. Cook them a day or two in advance and store in the fridge, then reheat briefly before topping the chicken.
What if I don't have beef stock concentrate?
Use about 1/2 cup beef broth instead and simmer the onions a minute longer to concentrate the flavor.
How do I know the chicken is done?
An instant-read thermometer should hit 165 degrees F at the thickest part, and the juices should run clear.
Can I use pre-shredded cheese?
Absolutely. Pre-shredded mozzarella melts fine here, though freshly grated melts a touch smoother.

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