French Onion Rigatoni Skillet: One Pan, Golden Cheese Crust

Sweet, slow-cooked onions meet tender rigatoni and a crackling layer of Gruyère in one cast-iron skillet. The flavor of French onion soup arrives as a hearty pasta dinner, with only one pan to wash afterward and a golden, blistered cheese crust on top.

French onion soup has always been a dish built on patience. Thin onions cooked in butter slowly turn from pale to deep amber, and that sweetness is what gives the broth its character. This recipe carries the same idea into a skillet of rigatoni. The onions are cooked down until they are jammy and golden-brown, then garlic and thyme go in for aroma.

Cooked pasta is stirred into the onions with broth and seasoning, so every piece absorbs the sweet, savory sauce. A layer of freshly grated Gruyère goes over the top, and the whole skillet goes into the oven until the cheese bubbles and browns in spots. The result is a saucy, comforting dinner served straight from the pan, with the same flavors you would expect from a bowl of French onion soup.

Ingredients

Why this recipe works

The onions do most of the work in this dish, so the cooking time matters. Cooking them over medium heat with butter lets their natural sugars slowly break down and caramelize, which gives a deep, sweet flavor that cannot be rushed.

Stirring every few minutes keeps the onions from scorching while the browned bits build up on the bottom of the pan. Those browned bits are full of flavor, and scraping them into the onions as they cook gives the sauce its rich color and taste.

Adding the pasta directly to the onion mixture, rather than cooking it separately, lets the rigatoni soak up the broth and the onion sugars. The pasta is cooked slightly under the package time because it keeps cooking in the sauce and in the oven. Finishing the dish in a hot oven sets the cheese into a golden, blistered crust while the pasta stays tender and saucy in the center, which is why the baking step is short but essential.

Notes and substitutions

Yellow onions are the best choice here because they caramelize into a sweet, deep flavor that holds up well to long cooking. Sliced evenly, they cook at the same rate and turn uniformly golden. Slicing them thin, rather than in thick rings, helps them break down into a silky texture that coats the pasta.

A heavy 12-inch cast-iron skillet holds heat well and goes straight from the stove to the oven, so you do not need to transfer anything. If your skillet is smaller, cook the onions in two batches and combine them before adding the pasta.

Gruyère is the classic cheese for French onion dishes because it melts smoothly and has a nutty, savory taste that complements the onions. Grate it yourself over a box grater, since freshly grated cheese melts more evenly than bagged shreds.

Rigatoni's wide, ridged tubes hold the sauce well, but penne or ziti work as well. A wooden spoon is useful for scraping the pan and for folding the cheese into the pasta without breaking the noodles. A colander is needed to drain the rigatoni before it goes into the skillet.

• Gruyère cheese: Swiss cheese or sharp white cheddar, grated
• low-sodium beef broth: low-sodium vegetable broth for a lighter onion flavor
• dry rigatoni: dry penne or ziti, cooked to the same tenderness

Equipment

• 12-inch cast-iron skillet
• Box grater
• Wooden cutting board
• Chef's knife
• Wooden spoon
• Colander