This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has hands; lacks a head but has a face. What is it?

Beneath the waves I swim and glide, In hidden depths, I choose to slumber. With silent breath, I roam the deepest trench, A metal beast where secrets slept.

Paths drawn on paper, Guiding wanderers afar, Folded universe.

My first part some slushy chow, My second what you're probably in right now. My whole rises quietly in forests dark, In many dishes my earthy flavors I impart.

I guard what’s precious, Whether beating or buried. What am I?