Before you read this it's important you understand the golden rule: It's never, EVER, under any circumstance, OK to open an unopened package of food that doesn't belong to you. It should be assumed that all the food listed below is from an already opened package.
19.A sliver of used pizza
18.Any type of chip
17.Anything in a Ziploc bag
16.One square from a candy bar
15.Milk
14.Any kind of spice
13.A shot of liquor
12.A small glass of wine
11.Any condiment
10.Olive oil
9.An egg or two
8.A baked good
7.A piece of any Easter or Christmas candy they receive from relatives
6.One bowl of cereal
5.A scoop of ice cream, but not like the "meat" of the work
4.A small plate of leftovers (depending on the situation)