In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add 1 large, thinly sliced yellow onion and sauté for about 25-30 minutes. Stir occasionally until the onions are soft and golden brown, releasing their sweetness. In the last 5 minutes of cooking, add 3 minced garlic cloves, cooking until fragrant. Season with salt and pepper to taste.

In a small saucepan, heat 3 tablespoons of olive oil over low to medium heat. Add 1 sliced garlic clove and gently infuse the oil for about 2 minutes until fragrant. Next, stir in 1 tablespoon of red chili flakes and 1 teaspoon of paprika. Allow the mixture to simmer for another 2-3 minutes before adding 1 teaspoon of soy sauce. Remove from heat and let the chili oil sit for a minute to deepen the flavors.

While the onions and chili oil are being prepared, bring a large pot of salted water to a boil. Add 12 ounces of your preferred pasta and cook according to package instructions until al dente, usually about 8-10 minutes. Before draining, reserve 1 cup of pasta water. Once cooked, drain the pasta and return it to the pot.

In the pot with the drained pasta, add the sweet caramelized onions along with their cooking oil. Drizzle the infused chili oil over the mixture and toss gently to combine, ensuring each piece of pasta is coated. If the pasta appears too dry, gradually mix in the reserved pasta water until you achieve your desired consistency.

To elevate your dish, generously sprinkle grated Parmesan cheese over the pasta. Add freshly chopped basil or parsley for a pop of color and freshness. If you prefer extra heat, feel free to add more chili flakes on top. Serve warm.