Pat's Café is by far the best breakfast in San Francisco.
We visited here 3 times for breakfast and found it to be a fantastic place to eat, the menu selection is very good and the food is tasty.
The service is very good and it's a clean and tidy premises.
It's very popular with the locals and a bit off the beaten track so you don't tend to get as many tourists as you would in a place like Pier 39 for example which is a nice change.
It's advisable to arrive before you want to actually eat on Saturday and put your name down on the list for a table as it can get busy.