Once water boils, add gemelli to pot. Cook, stirring occasionally, until al dente, 10-12 minutes. While gemelli cooks, pick half the basil from stems (leave the remainder on the stem and save for lunch). Roughly chop picked leaves or tear into smaller pieces with your hands. Once gemelli is done, scoop out and reserve ¼ cup pasta cooking water, then drain. TIP: Don’t put away the pot just yet; we’ll use it later.