I, too, finished the game in record time for me. So what do you do? Go back and attempt expert at all levels. Cannot get it for 46 (can for 47, 48).
For those of you stuck - you might pay a bit more attention to color seating. If you happen to get a 3X or 4X color seated, that is $100 per X to do that - really helps if you fall short. I found out, by accident, that usuing the chili sauce helps a certain slower customer - often if you use it, they order dessert - dessert if $100 and "perfect cooking" is $75 - so if you are "cooking" pay attention to grabbing it immediately.