Introduction

Caramelized Onion Pasta with Chili Oil is a delightful blend of sweet and spicy flavors that will elevate your weeknight dinner. This dish combines slowly caramelized onions with a fiery homemade chili oil, creating a perfect balance of richness and heat.

A skillet filled with a large amount of cooked spaghetti coated evenly with a reddish-orange sauce, likely tomato-based with spices. The pasta strands are mixed with small bits of what looks like mushrooms or ground meat, giving texture variety. Small green herb pieces, possibly parsley, are scattered on top, adding a pop of color. The skillet is sitting on a white marbled surface with a woman's hand grasping the skillet handle from the left side of the image. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

12 oz pasta (spaghetti, penne, linguine, or preferred shape)
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 (adjust to spice preference)
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: Thinly slice the onion into even rings. Heat 2 tablespoons of olive oil in a large, deep skillet over medium heat. Add the onions with a pinch of salt and cook, stirring occasionally, for 25-30 minutes until golden and soft. Five minutes before done, add the minced garlic and cook until fragrant. Season with salt and pepper and set aside.
Step 2: In a small saucepan, warm 3 tablespoons olive oil over medium heat. Add the thinly sliced garlic and sauté for 1-2 minutes until fragrant. Stir in red chili flakes and paprika, cooking for 2-3 minutes. Add soy sauce, stir, and simmer for 2 more minutes. Remove from heat and set aside.
Step 3: Bring a large pot of salted water to a boil. Cook the pasta until al dente following package instructions. Reserve 1 cup of pasta water, then drain the pasta.
Step 4: Combine the cooked pasta with the caramelized onions, stirring to coat well. Drizzle the chili oil over the mixture and toss to combine. Add reserved pasta water gradually if the pasta seems dry to loosen the sauce.
Step 5: Serve the pasta hot, garnished with grated Parmesan cheese and chopped fresh basil or parsley. Add extra chili flakes if desired for more heat.

Tips & Variations

Use long pasta shapes like spaghetti or linguine to let the chili oil coat each strand beautifully.
Adjust the chili flakes quantity to control the spiciness level to your taste.
For a vegan version, skip the Parmesan or use a plant-based alternative.
Add toasted pine nuts or walnuts for extra texture and flavor.

Storage

Store leftover pasta in an airtight container in the refrigerator for up to 3 days. Reheat gently in a pan with a splash of water or olive oil to prevent drying out. The chili oil flavor intensifies as it sits, so taste before adding extra seasoning when reheating.

How to Serve

The image shows a bowl of spaghetti pasta with a rich, creamy sauce, light brown in color with small bits of herbs and spices spread evenly throughout. The spaghetti is fully coated, slightly shiny with a smooth texture. On top, a few fresh green herb leaves are scattered as garnish. One side of the bowl holds two pieces of toasted bread, golden brown with a crisp texture. The bowl is white, held by a woman's hand, and all of this is placed 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 pre-made chili oil instead of making it from scratch?

Yes, you can use store-bought chili oil for convenience, but homemade chili oil offers a fresher and more balanced flavor with garlic and soy sauce infusions.

What type of pasta works best for this recipe?

Long pasta like spaghetti or linguine works best as the chili oil clings nicely to the strands, but penne or other shapes are also great if preferred.