In the melting pot that is Los Angeles two local holiday food traditions stand out. One is eating tamales during the Christmas season which obviously is inspired by Mexico and the many Mexican restaurants around the city. Even one of the local fast-food hot dog chains offers tamales during the holidays.
The second tradition is going to Chinatown to have dim sum (Chinese bite-size noodle/pastries) for mid-day dinner on Christmas Day which seems to have originated in the Jewish community.
Other people, including my non-Jewish family, have begun doing Christmas-in-Chinatown, too. No long hours in the kitchen and no leftover turkey for us!
So if you decide to visit Chinatown for dim sum (or any other reason) and haven’t been there recently, you will see color gone wild on buildings around the area. I think that the new Blossom Apartments next to the Metro station instigated the painting craze.