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Caramelized Onion Pasta with Chilli Oil Recipe

5 Stars 4 Stars 3 Stars 2 Stars 1 Star 4.1 from 67 reviews
  • Author: Kimberly
  • Prep Time: 10 minutes
  • Cook Time: 30 minutes
  • Total Time: 40 minutes
  • Yield: 4 servings
  • Category: Main Course
  • Method: Stovetop
  • Cuisine: Italian-Inspired
  • Diet: Vegetarian

Description

This Caramelized Onion Pasta with Chilli Oil is a flavorful vegetarian Italian-inspired dish featuring slowly caramelized onions and a spicy, aromatic homemade chilli oil. The pasta is perfectly coated with sweet, golden onions and a hint of smoky heat, topped with grated Parmesan or Pecorino for a savory finish. A comforting and elegant meatless meal ready in just 40 minutes.

Ingredients

Pasta and Onion Sauce

  • 8 ounces spaghetti or linguine
  • 2 tablespoons olive oil
  • 2 large yellow onions, thinly sliced
  • 1 tablespoon butter
  • 1 teaspoon sugar
  • ½ teaspoon salt
  • ¼ teaspoon black pepper
  • ¼ cup reserved pasta water
  • Grated Parmesan or Pecorino for serving

Chilli Oil

  • ¼ cup olive oil
  • 1–2 teaspoons red pepper flakes (adjust to heat preference)
  • 1 garlic clove, thinly sliced
  • ½ teaspoon smoked paprika (optional)
  • Pinch of salt

Instructions

  1. Cook the Pasta: Bring a large pot of salted water to a boil. Add the spaghetti or linguine and cook until al dente according to package instructions. Reserve ¼ cup of the pasta water, then drain the pasta and set it aside.
  2. Caramelize the Onions: In a large skillet, heat 2 tablespoons of olive oil over medium-low heat. Add the thinly sliced onions, butter, sugar, salt, and black pepper. Cook slowly, stirring occasionally, for 25–30 minutes until the onions become deeply golden and caramelized. Near the end, add a splash of the reserved pasta water to deglaze the pan and loosen the onions.
  3. Make the Chilli Oil: While the onions cook, heat ¼ cup of olive oil in a small saucepan over low heat. Add the red pepper flakes, thinly sliced garlic, smoked paprika (if using), and a pinch of salt. Let the mixture gently simmer for 2–3 minutes to infuse the flavors. Remove from heat and set aside.
  4. Toss Pasta with Onions: Add the cooked pasta to the skillet with the caramelized onions. Toss together, adding a bit more reserved pasta water if needed, to coat the noodles evenly with the onion sauce.
  5. Finish and Serve: Drizzle the prepared chilli oil over the pasta and toss again to combine the spicy flavors. Serve immediately with a generous topping of grated Parmesan or Pecorino and extra chilli oil if desired.

Notes

  • Add fresh greens like arugula, spinach, or chopped herbs at the end for a burst of freshness.
  • For extra protein, serve with a poached or fried egg on top.

Find it online: https://slsrecipes.com/caramelized-onion-pasta-with-chilli-oil-recipe/