Summarize this article in one sentence.
This is where the magic happens! As you freeze the slime, it will turn from a liquid to a semi-solid. Simply put the bowl into the freezer, and set the timer for 10 to 15 minutes. If the bowl is made from glass, make sure that it is freezer-safe. Let the bowl cool down to room-temperature before you freeze it.

Summary:
Freeze the slime for 10 to 15 minutes.