This 4-ingredient French onion chicken casserole is my weeknight answer to that cozy, bistro-style flavor without the time commitment of a full pot of caramelized onions. Classic French onion soup, which likely emerged from humble onion-and-bread peasant dishes in France, relies on deeply browned onions, rich stock, and a blanket of cheese. Here, we borrow that same sweet-savory onion profile and translate it into a hearty baked chicken dish. It’s the kind of recipe you pull out when you want something comforting and familiar, but you also need it to be practical: minimal prep, a short ingredient list, and enough richness to feel like you put in more effort than you actually did.

This casserole is quite rich and savory, so it pairs well with simple, bright sides that balance the depth of the onions and cheese. I like to serve it with a crisp green salad—think mixed greens, thinly sliced radishes, and a light vinaigrette—to cut through the richness. Buttered egg noodles or mashed potatoes are excellent for catching the oniony sauce, while roasted green beans or steamed broccoli add color and a bit of crunch. If you’d like to echo the spirit of French onion soup, add some warm crusty bread on the side for soaking up every last bit of the pan juices.

Servings: 4 servings

1.5 to 2 pounds boneless, skinless chicken breasts or thighs
1 (10.5-ounce) can condensed cream of chicken soup
1 (10.5-ounce) can condensed French onion soup
1 1/2 cups shredded Swiss or Gruyère cheese (about 6 ounces)

Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish or similar casserole dish.

Pat the chicken dry with paper towels and trim any excess fat. Arrange the chicken pieces in a single layer in the prepared baking dish.

In a medium bowl, whisk together the condensed cream of chicken soup and the condensed French onion soup until smooth and evenly combined. You do not need to add water; the condensed texture helps create a rich sauce as it bakes.

Pour the soup mixture evenly over the chicken, making sure each piece is well coated and the sauce is distributed around the pan.

Cover the baking dish tightly with foil and bake for 25–30 minutes, or until the chicken is just cooked through and reaches an internal temperature of 165°F (74°C).

Carefully remove the foil and sprinkle the shredded Swiss or Gruyère cheese evenly over the top of the chicken and sauce.

Return the casserole to the oven, uncovered, and bake for an additional 10–15 minutes, or until the cheese is fully melted, bubbling around the edges, and lightly golden in spots.

Remove from the oven and let the casserole rest for about 5–10 minutes before serving. This brief rest allows the sauce to thicken slightly and makes it easier to portion. Serve the chicken with plenty of the oniony pan sauce spooned over the top.