Before her name was known in every American household, Stewart worked on Wall Street for five years as a stockbroker. Before that, she was a model, booking clients from Unilever to Chanel.

"There were very few women at the time on Wall Street … and people talked about this glass ceiling, which I never even thought about," Stewart said in an interview for PBS's MAKERS series. "I never considered myself unequal, and I think I got a very good education being a stockbroker."

In 1972, Stewart left Wall Street to be a stay-at-home mom. A year later, she started a catering business.