Rosenfeld took her offer for British chocolatier Cadbury Plc hostile on Monday, submitting to its shareholders a $16.4 billion cash and stock bid rejected as derisory by the company's leadership.
The formal offer, submitted in time for a UK Takeover Panel deadline, caps two months of a steady waiting game by Rosenfeld that has punctured investor hopes of a much sweeter bid.
In her management of Kraft's business, Rosenfeld has already shown she is prepared to walk away from a proposition that did not suit the world's second-largest food company, or in some cases, her own ambitions.
For example, one of the reasons Kraft reported disappointing revenue last week, she said, was because the company stood its ground against retailers pushing for product deals that would have hurt Kraft's profits.
We've chosen to walk away and stand firm in a number of cases, Rosenfeld told Reuters last week. It is absolutely the right decision.
When she rolled out a new set of operational guidelines for her company early this year, Rosenfeld left no doubt as to what should be done with employees who stubbornly resisted.
You roll right over them, Rosenfeld said at the time.
On a personal level, Rosenfeld actually walked away from Kraft in 2003 after being passed over for the CEO post.
Analysts expect Rosenfeld to stick to that type of discipline to win Cadbury, especially as there has so far been no sign of a counter-bidder. The second-most powerful American businesswoman as ranked by Fortune magazine, must also answer to legendary investor Warren Buffett.
Buffett's Berkshire Hathaway Inc is Kraft's largest investor and has already warned her against overpaying for Cadbury.
A STEADY RISE IN THE FOOD INDUSTRY
Rosenfeld, who listed her childhood ambition as being president of the United States, has charted a steady rise in the food industry since earning a doctoral degree in marketing and statistics from Cornell University.
She rose through company ranks as General Foods became part of Philip Morris Cos, which later combined it with another acquisition, Kraft.
Rosenfeld eventually led the integration of Nabisco into the Kraft business and was part of the team that led Kraft's initial public offering from Philip Morris -- now Altria Group Inc -- in 2001.
After leaving Kraft in 2003, Rosenfeld became head of PepsiCo Inc's Frito-Lay snacks unit, where she pushed growth of healthier products.
Meanwhile, Kraft suffered through slow sales growth and a series of restructurings that cut into profits.
In 2006, Rosenfeld was brought back as CEO and became chairman in 2007. In three years at the helm she has pushed more money into marketing and product development that has helped to boost sales and recover some market share.
While Kraft has tried to focus on healthier foods, it has seen more success with indulgent treats like Oreo Cakesters.
Rosenfeld has also led Kraft through several acquisitions, such as the $7.82 billion purchase of French food group Danone's cereal and cookies business in 2007, as well as the divestiture of the Post Cereal business. In those deals, she earned a name for getting assets Kraft wanted at a reasonable price.
(Editing by Michele Gershberg and Maureen Bavdek)