I often find that Houdini wants to cook at inconvenient times. To stop this you can enter Manual Mode which is located in the bottom right of the UI.
To make toggling between Manual and Auto mode easier and quick it can be scripted and dedicated a hotkey.
Googling brought up this feed http://www.vfxoverflow.com/questions/toggle-update-mode-in-houdini which has a nice little script for doing this.
Here’s the python script:
As stated by Georg Kaltenbrunner on the forum you can add it to a shelf tool and then assign it a hotkey by ctrl+alt+shift clicking on the shelf tool