In the rich text editor:
@beaniepudge
In a comment:
[beaniepudge](https://chowlings.com/user/beaniepudge)
For Names and Avatars:
In the rich text editor:
%beaniepudge
In a comment:
[![beaniepudge's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/beaniepudge) [beaniepudge](https://chowlings.com/user/beaniepudge)