Amtrack runs a passenger train from Chicago, IL through to Los Angeles, CA. This is an almost 2 day trip, with meals provided in a dining car.
Since LA arrival is in the morning is breakfast served on the SW Chief before its arrival in LA?
Yes, it does have a breakfast available in the dining car, no reservations needed.
Breakfast starts at 6:30am and is normally available until 10:00am. If the train is on time, it should be arriving in LA sometime around 9:30am on the second morning and the breakfast service will end shortly before then.
You should still have plenty of time to head to the dining car between 6:30-7:00 and enjoy your breakfast for up to an hour. I know from experience (albeit about 3 years old now) that most passengers go in and pick up a bagel and coffee and wander back to their own cars. (We weren't supposed to do that, but no ever said anything.)