Walter Baker, the eldest son of Edmund Baker, tried to establish himself in a few different careers before settling down to manage and run the chocolate business that would eventually bear his name. As an 1811 graduate of Harvard, Walter had studied law. He soon left that profession and went into the very profitable woolen cloth business after war with England was declared in 1812. When the war ended three years later, Walter ventured south to teach and occasionally trade cloth in New Orleans, Louisiana. In 1818 Walter returned to Dorchester to become a partner in the family chocolate business.

Walter took his job seriously, making sure the business ran smoothly and accurately. He took an aggressive approach to tracking his correspondence and made copies of all his letters. Walter’s business acumen and attention to detail might be part of the reason Edmund decided to retire in 1823, leaving Walter to take full ownership that same year. Walter renamed the family business Walter Baker and Company, and by 1827 he started branding his chocolate “W. Baker,” replacing his father’s “E. Baker” brand. In the early 1830s Walter established relationships with more merchants up and down the east coast. And by 1840 Baker’s was shipping goods to clients as far north as Halifax, Nova Scotia, and Portland, Maine, and also to Philadelphia, Baltimore, and multiple ports in Virginia, Georgia, and as far south as New Orleans.

Walter Baker was a prolific letter writer and personally kept in contact with distributors, retailers, and occasionally even individual customers. He was concerned about the quality, reputation, and advertising of his chocolate products and looked for ways to develop the company and strengthen customer loyalty. He corresponded with distributors about marketing ideas, noting how attractive the foil wrapping of Baker’s Spiced Cocoa Sticks would look in store windows, or how chocolate tins could be reused for storage. Walter was very involved in how his products were advertised, and personally kept tabs on regional advertising campaigns. With one wholesale grocer in particular, Walter had concerns about a lack of ads and stated, “I do not see any advertisements of yours, although, perhaps, I may not look in the right newspapers. In what newspapers do you advertise? Advertising, I conceive, at proper seasons is the best mode of reaching both city and country traders.”

The 1840s proved to be full of many “firsts” for Baker’s. Walter headed up the introduction of new chocolate products, such as Spiced Cocoa Sticks, Homeopathic Chocolate, French and Spanish Chocolate, and Caracas chocolate. Baker’s Chocolate was delivered for the first time by train in 1843. And Walter established trade relationships in San Francisco at the same time people were making the rush to the California gold mines in 1849.

Closer to home, the 1840s brought additional family members into the company. One of Walter’s new hires was his brother-in-law, Sidney B. Williams, as a clerk in 1843. Walter's plan was to groom Williams in all areas of the company so that when Walter retired, Williams could easily become his successor. In May 1848 the old 1813 Baker mill built by Walter’s father Edmund burned. The interior was destroyed, and damage to the outer stone was so severe that it was necessary to take down the mill and rebuild. A surprising seven months later, the new mill, made of granite, was erected. It contained many fire-prevention features as well as new, prominently displayed signage advertising “W. Baker & Co., Established 1780.” Soon business was back to normal and Walter hired his step-nephew, Henry L. Pierce, as a clerk to both himself and Sidney Williams.

After thirty four years of running Baker’s Chocolate, Walter Baker died at the age of fifty-nine on May 7, 1852. In accordance with his will, the trustees of his estate leased the company to Sidney Williams, who continued operations under the name of Walter Baker & Company.