# What You’ll Need:
→ Pasta
01 - 12 ounces rigatoni or penne (about 3 cups dry)
→ Onions
02 - 3 large yellow onions, thinly sliced
03 - 2 tablespoons unsalted butter
04 - 1 tablespoon olive oil
05 - 1/2 teaspoon fine salt
06 - 1/4 teaspoon freshly ground black pepper
07 - 1 teaspoon granulated sugar
08 - 2 cloves garlic, minced
09 - 1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried)
→ Sauce & Assembly
10 - 1/2 cup dry white wine
11 - 2 cups vegetable broth
12 - 2 teaspoons Worcestershire sauce
13 - 1 tablespoon all-purpose flour
14 - 1 cup heavy cream
15 - 1 1/2 cups grated Gruyère cheese, divided
16 - 1/2 cup grated Parmesan cheese
17 - 1 tablespoon chopped fresh parsley, for garnish
# How To Make:
01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish and set aside.
02 - Bring a large pot of salted water to a rolling boil. Add pasta and cook until just shy of al dente according to package directions. Drain and reserve briefly.
03 - Heat a large skillet over medium heat. Add butter and olive oil until melted and shimmering. Add sliced onions, salt, pepper and sugar and stir to coat.
04 - Reduce heat to medium-low and cook the onions, stirring frequently, until deeply golden and caramelized, about 25–30 minutes. Adjust heat as needed to prevent burning.
05 - Add minced garlic and thyme to the onions and cook 1 minute until fragrant.
06 - Sprinkle flour over the onions, stir and cook 1 minute. Pour in the white wine, scraping up browned bits from the pan, and simmer 2 minutes to reduce slightly.
07 - Add the vegetable broth and Worcestershire sauce, bring to a gentle simmer and cook 2–3 minutes. Reduce heat to low and stir in the heavy cream and 1 cup of the Gruyère until the cheese melts and the sauce is smooth.
08 - Add the drained pasta and the grated Parmesan to the skillet and toss until the pasta is evenly coated with the sauce and the cheese is distributed.
09 - Transfer the pasta and onion mixture to the prepared baking dish. Evenly sprinkle the remaining 1/2 cup Gruyère over the top.
10 - Bake in the preheated oven 20–25 minutes, until the top is bubbly and golden-brown and the interior is heated through.
11 - Remove from oven, let rest 5 minutes, garnish with chopped parsley and serve warm.
