This New York–born boss showed nerves of steel over the past year. She bought a $370 million controlling stake in a Vietnamese snack maker, allowing Mondelēz access to manufacturing and distributing in that growing market. She elbowed away the unwanted attention of notorious corporate raider Nelson Peltz. And she OK’d a change in the recipe for Cadbury’s Creme Eggs, apparently incurring the wrath of everyone in the United Kingdom. Cry her a river: Rosenfeld doesn’t back down.