The year coming to an end was the 100th birthday of one of the best-known cooks who never existed: Betty Crocker. The name was developed in 1921 as a way of giving a personalized response to consumer product questions.

Because it was cheery and all-American, “Betty” was chosen as her first name. The last name Crocker was selected in honor of William Crocker of the Washburn-Crosby Company, one of the six big milling companies that merged to become General Mills. Her signature look came from a company secretary and it still appears on Betty Crocker products.

In just three years, in 1924 in Minneapolis, Betty acquired a voice. She made her debut at the nation’s first cooking show, the Betty Crocker Cooking School of the Air. Going nationwide later, 13 different actresses conducted the show working from radio stations across the country. The show ran for 24 years.

By 1936 it was necessary for Betty to have a face. Artist Neysa McMein gathered together all the company women in the...