while writing, butt-in-chair
dried coconut cubes (when I'm feeling fancy)
Cheetos (when I'm so not)
during little writing breaks to the kitchen*
guacamole + guac transfer device (aka chip/pita/cracker)
spoonfuls of ice cream
after I've typed THE END
adult beverages (mostly wine)
*not at the same time. Although. . . .
For famous writers it is/was:
lime popsicles (Joyce Maynard)
cold toast and stale coffee (John Steinbeck)
See their snacks, illustrated, here
What about you: what do you munch while you punch the keys?