Name: Caramelized Onion Pasta with Chilli Oil Recipe
Prep time: 10 min
Cook time: 40 min
Total time: 50 min
Cuisine: Italian
Ingredients: 12 oz (340g) pasta of your choice (spaghetti, fettuccine, or penne works well); Salt (for boiling pasta water); 2 large onions, thinly sliced; 2 tablespoons olive oil; 1 tablespoon butter; 1 teaspoon sugar (optional, to help caramelize); Salt and pepper, to taste; 1/4 cup olive oil; 1 tablespoon chili flakes (adjust based on preferred spice level); 1 garlic clove, minced; 1/2 teaspoon smoked paprika (optional); 1/2 teaspoon salt; Fresh parsley, chopped; Grated Parmesan cheese; Extra chili oil

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Introduction

This Caramelized Onion Pasta with Chilli Oil is a deliciously simple dish that balances sweet, savory, and spicy flavors. Perfect for a quick weeknight meal, it transforms everyday ingredients into something special with caramelized onions and a fragrant chili oil.

A white bowl filled with a neatly twirled nest of spaghetti coated in a shiny, light brown sauce. The pasta is mixed with small pieces of caramelized onion and scattered with bits of dark red chili peppers and finely chopped green herbs on top, creating a colorful contrast. The dish has a glossy texture, indicating a sauce infused with oil and spices, all set against a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Ingredients

12 oz (340g) pasta of your choice (spaghetti, fettuccine, or penne works well)
Salt (for boiling pasta water)
2 large onions, thinly sliced
2 tablespoons olive oil
1 tablespoon butter
1 teaspoon sugar (optional, to help caramelize)
Salt and pepper, to taste
1/4 cup olive oil
1 tablespoon chili flakes (adjust based on preferred spice level)
1 garlic clove, minced
1/2 teaspoon smoked paprika (optional)
1/2 teaspoon salt
Fresh parsley, chopped (optional)
Grated Parmesan cheese (optional)
Extra chili oil (optional)

Instructions

Step 1: In a large skillet, heat 2 tablespoons of olive oil and 1 tablespoon of butter over medium-low heat.
Step 2: Add the thinly sliced onions and a pinch of salt. Stir occasionally to cook evenly.
Step 3: Sprinkle 1 teaspoon of sugar over the onions if using, to help caramelize. Cook for 25-30 minutes, stirring occasionally, until the onions turn deep golden-brown. Set aside.
Step 4: In a small saucepan, heat 1/4 cup olive oil over low to medium heat. Add minced garlic and chili flakes.
Step 5: Let the garlic infuse for 1-2 minutes, stirring occasionally, but be careful not to burn it.
Step 6: Stir in smoked paprika and 1/2 teaspoon salt, then remove from heat and set aside.
Step 7: Bring a large pot of salted water to a boil and cook pasta according to package instructions until al dente, about 8-10 minutes.
Step 8: Drain the pasta, reserving about 1/2 cup of the cooking water.
Step 9: Return the skillet with caramelized onions to medium heat. Add the cooked pasta and toss to combine. Add reserved pasta water as needed to coat the pasta evenly.
Step 10: Pour the chili oil over the pasta and toss well to coat all strands with the spicy oil.
Step 11: Serve immediately, garnished with chopped parsley and grated Parmesan cheese if desired. Drizzle with extra chili oil for more heat.

Tips & Variations

Use a mix of red and yellow onions for more complex sweetness in the caramelization.
Adjust chili flakes to suit your preferred spice level, or substitute with fresh chopped chili for a different texture.
Add a squeeze of lemon juice before serving to brighten the flavors.
Try tossing in toasted pine nuts or walnuts for a crunchy contrast.

Storage

Store leftover pasta in an airtight container in the refrigerator for up to 3 days. Reheat gently in a skillet with a splash of water or olive oil to prevent sticking. The chili oil may separate upon cooling, so stir well before serving.

How to Serve

A close-up of a plate with one main layer of thick spaghetti pasta coated in a light brown sauce, sprinkled with small red chili flakes and some grated cheese. The top is scattered with fresh green parsley leaves and dark, thin slices of caramelized onion. The pasta sits in a white bowl on a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use frozen onions for caramelizing?

Fresh onions work best for caramelizing as frozen ones release extra moisture, which can slow down the browning process. If using frozen, thaw and drain them well before cooking.

Is this dish suitable for vegans?

You can make this recipe vegan by omitting the butter and Parmesan cheese or substituting with plant-based alternatives. Use olive oil instead of butter for cooking the onions.