Waitress (Rosa)
From Tardis Wiki, the free Doctor Who reference
A waitress worked at Slim's Bar in Montgomery, Alabama in 1955.
She noticed the Thirteenth Doctor and her companions Ryan Sinclair, Yasmin Khan and Graham O'Brien in the diner. She refused Ryan and Yasmin service, labelling the former as a "negro" and mistaking the latter as being Mexican rather than a British woman of Pakistani heritage.
The waitress told the group that they would have to eat somewhere else. Following this, the Doctor and her companions left. (TV: Rosa)