On her sixth album, Missy Elliott continues to push forward as if still out to prove something. The Cookbook finds her acknowledging hip-hop’s past (guests include Grand Puba and Slick Rick) and present (Ciara and M.I.A.) while nearly running to get around the next corner. Like Jay-Z at his best, she blurs the lines between party-ready and thoughtful, sounding up-close and personal even when a track is packed with other stars. Even her old tricks sound thrilling, as when the heavily electro single “Lose Control” breaks into a completely different rhythm midway through. Not only does Missy more than represent for great hip-hop, she’s doing a hell of a lot for the whole of pop music.