# Components:
→ Pasta
01 - 340 g rigatoni or penne
→ Onions
02 - 3 large yellow onions, thinly sliced
03 - 28 g unsalted butter
04 - 15 ml olive oil
05 - 2.5 g fine salt
06 - 0.6 g freshly ground black pepper
07 - 4 g granulated sugar
08 - 2 garlic cloves, minced
09 - 1 g fresh thyme leaves (approximately)
→ Sauce & assembly
10 - 120 ml dry white wine
11 - 480 ml vegetable broth
12 - 10 ml Worcestershire sauce
13 - 8 g all-purpose flour
14 - 240 ml heavy cream
15 - 150 g grated Gruyère, divided (about 100 g for sauce, 50 g for topping)
16 - 50 g grated Parmesan cheese
17 - 1 tbsp (≈3 g) chopped fresh parsley, for garnish
# Directions:
01 - Heat oven to 200°C and lightly grease a 23 x 33 cm baking dish.
02 - Bring a large pot of well-salted water to a boil, cook the pasta until just shy of al dente per package directions, drain and set aside.
03 - In a large skillet over medium heat, melt the butter with the olive oil. Add the sliced onions, salt, pepper and sugar and cook, stirring frequently, until the onions are deeply golden and caramelized, about 25–30 minutes.
04 - Stir in the minced garlic and thyme and cook for 1 minute until fragrant.
05 - Sprinkle the flour over the onions, cook for 1 minute, then pour in the white wine, scraping the pan to release browned bits; simmer for 2 minutes.
06 - Add the vegetable broth and Worcestershire sauce, bring to a simmer and cook 2–3 minutes to meld flavors.
07 - Reduce heat to low and stir in the heavy cream and 100 g grated Gruyère until melted and smooth.
08 - Fold the cooked pasta and the grated Parmesan into the skillet, tossing gently to coat evenly with the sauce.
09 - Transfer the pasta mixture to the prepared baking dish and evenly sprinkle the remaining 50 g Gruyère over the top.
10 - Bake in the preheated oven until the casserole is bubbly and the cheese is golden brown, 20–25 minutes. Allow to rest briefly after removing from oven.
11 - Scatter the chopped parsley over the baked dish and serve warm.
