The cheesy substance that exists inside your travel mug lid and/or it's associated pouring mechanism. It unknowingly builds up over time from lack of daily cleaning. After an extended period of time fungus will grow morphing said item into "Travel Chef Salad".
Brah: Dude, don't EVER lend me your travel mug again!

Dude: Why not brah?
Brah: The lid was so caked with coffee cheese I coulda added Macaroni and had dinner!!!
by Laika 2 February 16, 2015
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