Paul Giamatti traded a fancy dinner for a good ol' burger and fries to celebrate his Golden Globes win ... beelining straight to an In-N-Out after the awards ceremony Sunday evening.
The suited and booted actor dined at the popular fast food restaurant in Westwood ... his shiny Best Actor trophy, which he won for 'The Holdovers', perched alongside trays of food.
Writer Evan Ross Katz shared the IG snap ... writing, "Paul Giamatti celebrating his Golden Globe win at In-N-Out. King. Absolutely no notes."
Paul's low-key sighting comes after finding himself the center of attention while collecting his awards earlier onstage.
He placed focus elsewhere during his acceptance speech, though ... paying thanks to teachers -- especially as he plays a stubborn teacher in the movie.
With the GGs setting the tone for the rest of the award season, it looks like Paul could be in and out of In-N-Out a whole lot more this year!