Name: Caramelized Onion Pasta with Chili Oil Recipe
Prep time: 10 min
Cook time: 40 min
Total time: 50 min
Cuisine: Italian
Ingredients: 12 oz pasta (spaghetti, penne, or linguine); 2 tablespoons olive oil; 1 large yellow onion, thinly sliced; 3 cloves garlic, minced; Salt and pepper, to taste; 3 tablespoons olive oil (extra virgin preferred); 1 tablespoon red chili flakes; 1 teaspoon paprika; 1 small garlic clove, thinly sliced; 1 teaspoon soy sauce; Grated Parmesan cheese; Fresh basil or parsley, chopped; Extra chili flakes (optional)

Jump to Recipe

Introduction

Caramelized Onion Pasta with Chili Oil is a flavorful and comforting dish that balances sweetness, spice, and umami beautifully. The slow-cooked onions add depth, while the homemade chili oil brings a lively kick. It’s perfect for a cozy dinner that feels both simple and special.

A close-up view of a plate filled with thin spaghetti noodles coated in a glossy light brown sauce, topped with small bits of dark red chili flakes and tiny green herb pieces scattered around. The noodles have a soft, slightly oily texture and are twisted in gentle loops. Black pepper and white sesame seeds are sprinkled evenly over the top to add texture. The plate is white and sits on a white marbled surface, enhancing the warm colors of the dish. photo taken with an iphone --ar 4:5 --v 7

Ingredients

12 oz pasta (spaghetti, penne, linguine, or your choice)
2 tablespoons olive oil (for sautéing onions and garlic)
1 large yellow onion, thinly sliced
3 cloves garlic, minced
Salt and pepper, to taste
3 tablespoons olive oil (for chili oil)
1 tablespoon red chili flakes
1 teaspoon paprika
1 small garlic clove, thinly sliced
1 teaspoon soy sauce
Grated Parmesan cheese, for garnish
Fresh basil or parsley, chopped, for garnish
Extra chili flakes (optional, for extra heat)

Instructions

Step 1: Prepare the onions by slicing them into even rings. Heat 2 tablespoons of olive oil in a large skillet over medium heat. Add the onions with a pinch of salt and cook, stirring occasionally, for 25–30 minutes until golden and soft.
Step 2: Add the minced garlic about 5 minutes before the onions are done. Cook until fragrant, then season with salt and pepper. Set aside.
Step 3: In a small saucepan, warm 3 tablespoons of olive oil over medium heat. Add the thinly sliced garlic and sauté for 1–2 minutes until fragrant but not browned.
Step 4: Stir in red chili flakes and paprika, cooking for 2–3 minutes until aromatic. Pour in the soy sauce, stir, and simmer for another 2 minutes. Remove from heat and set aside.
Step 5: Meanwhile, bring a large pot of salted water to a boil. Cook the pasta according to package instructions until al dente. Reserve 1 cup of pasta water, then drain the pasta.
Step 6: Combine the pasta with the caramelized onions in a large bowl or the skillet. Toss to coat the noodles well with the sweet onions.
Step 7: Drizzle the chili oil over the pasta and toss again to evenly distribute. If the pasta seems dry, add reserved pasta water a little at a time to loosen the sauce.
Step 8: Garnish with grated Parmesan cheese and chopped fresh basil or parsley. Sprinkle additional chili flakes if you like extra heat.
Step 9: Serve hot immediately, either on its own or alongside a fresh salad for a complete meal.

Tips & Variations

Use long pasta shapes like spaghetti or linguine for the best texture with the sauce.
Adjust chili flakes according to your heat preference to make it mild or spicy.
For a vegan option, skip the Parmesan or use a plant-based cheese alternative.
Adding a squeeze of fresh lemon juice just before serving can brighten the flavors.

Storage

Store any leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in a skillet over low heat, adding a splash of water or reserved pasta water to loosen the sauce and prevent sticking. This pasta is best enjoyed fresh for optimal texture and flavor.

How to Serve

A close-up view of a plate with one main layer of cooked spaghetti noodles coated in a shiny, oily sauce, topped with small pieces of red chili flakes, black pepper, and finely chopped green herbs scattered evenly. The noodles are twisted loosely in the center of a white plate, resting on a white marbled texture. The overall color shows warm golden brown tones with a glistening surface, making the dish look flavorful and slightly spicy. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use pre-made chili oil instead of making it from scratch?

Yes, you can substitute with good quality store-bought chili oil, but the homemade version infuses fresh garlic and spices, offering more depth and a tailored heat level.

How do I know when the onions are properly caramelized?

The onions should be soft, deeply golden brown, and sweet in aroma and taste. This process takes patience, about 25 to 30 minutes over medium heat, with occasional stirring to prevent burning.