This oven baked 5-ingredient French onion pasta is the kind of rich weekend comfort meal my grandmother used to slide onto the table in a heavy ceramic baking dish. She taught me that you don’t need a long ingredient list to make something that feels special—just patience with the onions and plenty of cheese. The pasta bakes up with dark, jammy onions tucked into every nook of the rigatoni, and when you scoop it out, the cheese stretches in long, gooey strands. It’s simple enough for a busy Saturday, but cozy and indulgent enough that my family always scrapes the dish clean.
Serve this French onion pasta straight from the hot baking dish with a big metal spoon for scooping. It pairs nicely with a crisp green salad dressed in a light vinaigrette to balance the richness, and some warm crusty bread or garlic toast to catch any cheesy onion bits left in the pan. A sparkling water with lemon or a simple iced tea keeps it family-friendly, while adults who enjoy wine might like a glass of dry white or light red alongside. Let the pasta sit 5–10 minutes before serving so it sets slightly and is easier to scoop into generous bowls.
Oven Baked 5-Ingredient French Onion PastaServings: 6
Ingredients
2 pounds yellow onions, thinly sliced
3 tablespoons unsalted butter
12 ounces dry rigatoni pasta
3 cups low-sodium beef broth
3 cups shredded Gruyère or Swiss cheese (about 8–9 ounces)
1 teaspoon kosher salt (optional, to taste)
1/2 teaspoon black pepper (optional, to taste)
Directions
Preheat your oven to 375°F (190°C). Lightly butter or spray a medium to large ceramic baking dish (about 9x13 inches or similar) and set it aside.
Caramelize the onions: In a large, heavy skillet or Dutch oven, melt the butter over medium heat. Add the sliced onions and a pinch of salt if using. Cook, stirring every few minutes, until the onions turn deep golden brown and very soft, 30–40 minutes. If they start to scorch, lower the heat and add a tablespoon of water to loosen the browned bits. This slow caramelizing step is what gives the pasta that rich, French onion soup flavor my grandmother loved.
While the onions cook, bring a large pot of salted water to a boil. Add the rigatoni and cook 2–3 minutes less than the package directions for al dente (the pasta will finish in the oven). Drain well and set aside.
When the onions are deeply caramelized and jammy, pour in the beef broth and stir, scraping up any browned bits from the bottom of the pan. Let the mixture simmer for 3–5 minutes so the flavors come together. Taste and add additional salt and black pepper if needed.
In a large bowl or the drained pasta pot, combine the undercooked rigatoni with the hot onion-broth mixture. Stir gently until all the pasta is coated and the onions are distributed throughout.
Layer the pasta and cheese: Spread half of the onion-coated pasta into the prepared ceramic baking dish. Sprinkle with half of the shredded Gruyère or Swiss cheese. Add the remaining pasta in an even layer, then top with the remaining cheese, making sure to cover the surface so you get that bubbly, gooey top.
Cover the baking dish tightly with foil and bake at 375°F (190°C) for 15 minutes to let the pasta finish cooking and absorb the broth.
Remove the foil and continue baking for another 15–20 minutes, or until the cheese is fully melted, bubbling around the edges, and starting to brown in spots. If you like a deeper golden top, you can broil on high for 1–3 minutes, watching closely so it doesn’t burn.
Carefully remove the baking dish from the oven and let the pasta rest for 5–10 minutes. This helps the sauce thicken slightly and makes it easier to scoop clean portions. Serve straight from the ceramic dish with a sturdy metal serving spoon, digging down to catch the dark caramelized onions and pulling up big, cheesy stretches of rigatoni just like my grandmother used to.
Refrigerate any leftovers in a covered container within 2 hours of baking. Reheat individual portions in the microwave or cover the baking dish with foil and warm in a 325°F (165°C) oven until heated through.
Variations & Tips
To keep this close to my grandmother’s style, I stick to the five main ingredients: onions, butter, pasta, beef broth, and cheese. The salt and pepper are optional helpers for seasoning and don’t change the simple spirit of the dish. For picky eaters who aren’t sure about visible onions, you can chop the caramelized onions a bit smaller before adding the broth so they blend in more with the pasta. If beef broth isn’t an option, you can swap in vegetable or chicken broth, though the flavor will be a bit lighter. For a milder taste, use half Gruyère and half mozzarella, or even all mozzarella for kids who prefer a stretchy, familiar cheese. If you need to plan ahead, you can caramelize the onions up to 2 days in advance and store them in the fridge; warm them gently with the broth before mixing with the pasta. For a heartier version, stir in leftover shredded roast beef or rotisserie chicken when you mix the pasta and onions. Food safety tips: Always cook the onions thoroughly until they are soft and deeply browned, but not burnt. Keep hot foods out of the temperature danger zone by refrigerating leftovers within 2 hours of baking. If you add any meat or use homemade broth, make sure it has been cooked and stored properly and reheat leftovers to at least 165°F (74°C) before serving. Discard any leftovers that have been left at room temperature for more than 2 hours.
