Bring a large pot of water to a rolling boil. Add 1 tablespoon of salt. Add the spaghetti and cook according to package directions until al dente (usually 8-10 minutes).

Before draining the spaghetti, reserve about 1/2 cup of the starchy pasta water. Drain the spaghetti and set aside.

While the spaghetti is cooking, heat the extra virgin olive oil in a large skillet or frying pan over medium-low heat. Add the thinly sliced garlic and red chili flakes.

Sauté gently for 3-5 minutes, stirring occasionally, until the garlic is fragrant and lightly golden. Be careful not to burn the garlic, as it will become bitter.

Add the cooked and drained spaghetti directly into the skillet with the garlic and chili oil. Pour in about 1/4 cup of the reserved pasta water.

Toss everything together using tongs, allowing the pasta to absorb the flavors and the sauce to emulsify. If the pasta seems too dry, add a little more pasta water, one tablespoon at a time, until a light, glossy sauce forms.

Stir in the finely chopped fresh parsley. Season with salt and freshly ground black pepper to taste. Toss for another minute until everything is well combined and heated through.

Serve immediately, garnished with extra fresh parsley and grated Parmesan cheese, if desired.