01 -
In a large skillet, warm the olive oil and butter over medium-low heat. Add sliced onions and a pinch of salt. Cook slowly, stirring occasionally, until onions are softened and deeply golden, about 25 to 30 minutes. Sprinkle sugar if using to assist with caramelization. Adjust seasoning with salt and black pepper to taste. Set aside.
02 -
In a small saucepan over low to medium heat, combine olive oil, minced garlic, and chili flakes. Infuse the aromatics, stirring, for 1 to 2 minutes, ensuring the garlic does not brown. Add smoked paprika if desired, and salt. Stir to combine, then remove from heat and set aside.
03 -
Bring a large pot of salted water to a boil. Add the pasta and cook according to package instructions until al dente, typically 8 to 10 minutes. Reserve 120ml pasta water, then drain.
04 -
Return the skillet with caramelized onions to low heat. Toss in the drained pasta, mixing to distribute onions evenly. Add a splash of reserved pasta water as needed to emulsify and coat the noodles.
05 -
Drizzle the prepared chili oil over the pasta and toss thoroughly, ensuring the noodles are well-coated with the infused oil.
06 -
Plate the pasta, topping with fresh parsley and grated Parmesan as desired. Drizzle with extra chili oil for additional heat and serve immediately.