Meanwhile, heat the olive oil over medium heat in a pot large enough to hold the pasta, such as a 12-inch saute pan or a large, shallow pot. Add the garlic and cook for 2 minutes, stirring frequently, until it just begins to turn golden on the edges-don’t overcook it! Add the red pepper flakes and cook for 30 seconds more. Carefully add the reserved pasta-cooking water to the garlic and oil and bring to a boil. Lower the heat, add 1 teaspoon of salt, and simmer for about 5 minutes, until the liquid is reduced by about a third.