IRS Reporting for Private Money Interest Earned

[Chris Licavoli]

I am happy to announce that I have just completed my first flip project using private money.  The project was successful and the investor received a check at closing for his principal plus interest.  He was extremely happy to say the least, but I believe I have created an obligation for myself to report his interest earned to the IRS.  I have no idea how to do that or if I do have to do that.  Are there any experienced PM users out there that can offer some advice.  Is this something my CPA will do for me or should I do it?  How do you do it? 

Thanks in advance!