How to lock PC after Steam Link session?

[Iacomus]

Hello, I am attempting to use Steam Link and want to lock my pc when I am done, however I cannot interact with my desktop at all when using steam link. I can minimize steam, but I can't interact with anything so that I can lock my machine. I don't want to shut it down, restart it, or suspend it, in the event I want to start another session. But I don't want to just leave my machine unlocked either.

Am I missing something? Is there some easy way to do this that I have overlooked?