Not just a cultural center and not just a membership club, Rainbow Sign was also a restaurant. Many different chefs manned the kitchen over the years, some staying longer than others, some rerouted for their propensity to drink and not arrive to work. On such occasions Mary Ann Pollar herself, or her right-hand man Charles Brown might jump behind the stove and keep the kitchen running.

Chef Joseph was by all accounts a responsible cuisinier; he also ran a nearby restaurant on 7th St. in Oakland. When columnist and Rainbow Sign board member Edith Austin returned from a trip to Africa, she made this observation about what she missed most on her trip:

I spent five glorious weeks in East Africa — and you wanta believe it when I say I missed sticking my nose into everybody’s business in the Bay Area. But you want to know what I missed most??… JOSEPHS of Rainbow Sign’s deep fried chicken and cornbread ends. Not that they don’t have fried chicken in Africa — the first place I saw on Kenyatta Drive in Nairobi, Kenya was a Kentucky Fried Chicken house — but you and I know the Colonel ain’t no JOSEPH.

In the later years of Rainbow Sign, the retired Henry Pollar took over the cooking. Charles Brown ran the front of house and staffed the restaurant with several recent Cal grads and two recently paroled convicts. In addition to being a center for education in the arts, Rainbow Sign was also a place to learn a trade.