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