Bring a large pot of salted water to a boil and add the spaghetti. Cook according to package instructions until al dente, then drain and set aside, reserving a cup of pasta water.
Heat the olive oil in a skillet over medium heat until shimmering and slightly fragrant. Add the thinly sliced garlic and cook, stirring often, until it turns golden and fragrant, about 1-2 minutes.
Sprinkle in the red chili flakes and cook for another 15-20 seconds until the chili releases its aroma, creating a spicy, smoky scent that fills the kitchen.
Add the cooked pasta to the skillet, tossing quickly to coat it evenly in the spicy garlic oil. If the mixture looks dry, add a splash of the reserved pasta water to loosen it up and create a glossy sauce.
Season with salt to taste, adjusting the overall flavor. Toss everything together once more to ensure the spices and oil are evenly distributed.
Transfer the pasta to serving plates, garnish with freshly chopped parsley, and serve immediately to enjoy the vibrant aroma and fiery flavor.
