Doris was a waitress in Broward, Florida.
Doris was waitressing in the diner in which Sam and Dean repeatedly ate breakfast while trapped in a time loop that only Sam was aware of, and during which Dean died every time. Every looped Tuesday, she cheerfully brought Dean the daily special (pig 'n a poke), a side order of bacon and a coffee--with the exception of one instance when Dean changed his side order to sausage, only to choke on the first bite.
Instead of giving her his breakfast order on the "100th Tuesday in a row" of this ordeal, an exasperated and grumpy Sam told Doris he would like her to log in some more hours at the archery range, because she was a "terrible shot." She worriedly asked him how he knew, and he dryly replied "lucky guess," suggesting that she was responsible for at least one of Dean's deaths. When she returned to the table with their order, Sam casually caught the hot sauce bottle that perpetually fell from her tray and slammed it on the table without so much as turning his head.