Meanwhile, heat a large straight-sided skillet over medium heat. Add the olive oil and pancetta. Cook, stirring often with a wooden spoon, until the pancetta is crisp, about 10 minutes. Add the pepper and toast it, stirring often, for about a minute, or until fragrant. Add 1⁄2 cup of the reserved pasta water and scrape up any bits that are sticking to the bottom of the skillet.