http://sqlfiddle.com/#!3/3973f/1
Edit: I'm not allowed to reply just yet, so I'll post here.
You need to add the boss first to the employee table with a NULL bossID.
Then you add another employee that has a bossID that refers to that last added record.
> DEFAULT (IDENT_CURRENT('dbo.Employees'))
on the BossID column. Been awhile (years) since I've worked with SQL Server.
http://sqlfiddle.com/#!3/3973f/1
Edit: I'm not allowed to reply just yet, so I'll post here.
You need to add the boss first to the employee table with a NULL bossID.
Then you add another employee that has a bossID that refers to that last added record.