Description
A simple, flavor-packed pasta that pairs deeply caramelized onions with a fragrant chili oil. The onions give a rich, syrupy sweetness while the chili oil adds warmth and subtle smokiness — perfect for a cozy weeknight meal.
Ingredients
For the pasta
- 12 oz (about 340 g) pasta — spaghetti, linguine, penne, or your favorite shape
- 2 tbsp olive oil
- 1 large yellow onion, thinly sliced
- 3 garlic cloves, minced
- Salt and freshly ground black pepper, to taste
For the chili oil
- 3 tbsp olive oil (extra-virgin preferred)
- 1 tbsp red chili flakes (adjust to heat preference)
- 1 tsp smoked or sweet paprika
- 1 small garlic clove, thinly sliced
- 1 tsp soy sauce
To finish
- Freshly grated Parmesan cheese, for serving
- Fresh basil or parsley, chopped, for garnish
- Extra chili flakes (optional)
Instructions
-
Prepare the onions
Heat 2 tablespoons olive oil in a wide skillet over medium heat. Add the sliced onion and a pinch of salt. Cook the onions slowly, stirring occasionally so they brown evenly — this usually takes about 25–30 minutes. Reduce the heat if they start to blacken. When the onions are soft and deeply golden, stir in the minced garlic for the final 3–4 minutes and season with pepper. Set the pan aside. -
Make the chili oil
While the onions cook, warm 3 tablespoons olive oil in a small saucepan over medium heat. Add the sliced garlic and let it scent the oil for a minute or two without letting it brown. Stir in the red pepper flakes and paprika and cook briefly until they release their aroma (1–3 minutes). Add the teaspoon of soy sauce, give everything a stir, then remove from heat and let the oil rest so the flavors infuse. -
Cook the pasta
Bring a large pot of salted water to a rolling boil. Add the pasta and cook according to package directions until al dente. Before draining, scoop out and reserve 1 cup of the starchy pasta water. Drain the pasta. -
Combine pasta and onions
Return the drained pasta to the pan or into the skillet with the caramelized onions. Drizzle the chili oil over the noodles and toss thoroughly so the oil and onions coat every strand. If the mixture seems dry, add the reserved pasta water a splash at a time until you reach a glossy, saucy consistency. -
Finish and serve
Plate the pasta and sprinkle generously with grated Parmesan. Scatter chopped basil or parsley over the top and, if you like extra heat, a few more chili flakes. Serve immediately while hot.
Notes
- Tips & swaps
- Be patient when caramelizing. Low-and-slow heat brings out the onions’ natural sugars; rushing will give you browned, not caramelized, onions.
- Reserve pasta water — that starchy liquid helps bind the sauce to the pasta for a silky finish.
- Make it vegan by skipping the Parmesan or using a plant-based alternative.
- Add vegetables like sautéed mushrooms, wilted spinach, or roasted cherry tomatoes for extra texture.
- For protein, fold in grilled shrimp, seared chicken, or crispy tofu.
- Storage
- Refrigerate leftovers in an airtight container for up to 3 days. Reheat gently in a skillet with a splash of water or olive oil to loosen the sauce.
Nutrition
- Calories: 450 kcal
- Fat: 20g
- Carbohydrates: 55g
- Protein: 12g