This machine allows me to mix a single cookie and vary the recipe for each cookie on the sheet. Hence, I can test many different recipe variations with one batch of ingredients in one afternoon. The butter is dispensed in solid form at room temperature from the metal syringe. The eggs (yellow) are in the glass syringe. Music: Cool Vibes - Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0/