すりおろしとく
摺り下ろしとく
suri oroshitoku

Godan Verb (su)
Aspectual Auxiliary

Preparatory: doing something in advance or leaving it done of すりおろす

1. Preparing beforehand; Pre-processing; (For food) Grating/mincing in advance

Preparatory Aspect
Colloquial
Usually Written in Kana