How to create Blu-Ray from previous files?

Question

Back in November of 2010 thefifthlion posted a similar question, but the thread was archived so I could not post a follow up in that same thread.
My question is similar:  how to create a Blu-Ray from previous Compressor files.  His answer was to create a disc image by selecting "Hard Drive" from the Output Device pop up menu.  Then use Toast or Disc Utility to burn the copies.  Fine, but here's my revised question to that:
Compressor just spent nearly 20 hours compressing a 2+ hour video with "Create Blu-Ray" selected for the When Job Completes.  Before it completed the Blu-Ray burner apparently fell asleep or went offline somehow because the computer wouldn't recognize the drive by the time Compressor was done.  So I had no choice but to selct "Cancel Burn" and stop the process, restart the computer, and get the Blu-Ray burner back online.
You probably know where I'm going with this.  I now have two files on my desktop - the video and the audio file created of the project from Compressor.  BUT WHAT CAN I DO WITH THOSE FILES NOW?  Needless to say I don't want to go through the entire 20 hour process again - only to have the same thing happen with the burner drive.  As per the below paragraph (copied from thefifthlion's original post in November) is this the best way to burn Blu-Rays in Compressor?  Always create a disc image rather than burn right away... and then use a third party burner like Toast 10 or Disc Utility to burn the disc?  I can't believe Compressor doesn't have an option to open the project again and burn a Blu-Ray straight away.
> Output Device pop-up menu: Use this pop-up menu to choose the device to format to. The pop-up menu displays a list of your system’s suitable output devices, including optical drives and the computer’s hard disk. Each device also includes the words Blu-ray or AVCHD to indicate which type of disc it creates. Choose Hard Drive to create a disk image (.img) file that you can burn to Blu-ray Disc media at a later time using the Disk Utility application (available in the Utilities folder). Other settings may change depending on the device you choose.
Thanks very much for any feedback.
Eric

Answer 1

Follow up question:
I went through the process again (approx 20 hours!! ) and this time made the video a disc image.  I don't have Toast (though I think it might be time to get it) but I keep reading that Disc Utility can burn a Blu Ray using that disc image.  So, I went through another multi hour process to burn that 20+ gig file onto a Blu Ray, but it appears that it didn't burn it as a playable disc, rather, more like it put the file on the disc as data files.  All the info is there, 20 some gigs, I can see all the files, but the disc doesn't play.
Now I apologize if it's a silly question if it's known that you can't make a playable blu ray with Disc Utility, but I don't know either way, that's just what I've read and this is the first time I've tried it. 
Soooooooo, if I always make a disc image, should I just get Toast and use that to make the blu ray?
By the way, a brief update:  the whole reason this thread came up was because my Pioneer blur ray burner goes offline (sleep) after an hour or so and doesn't come back or wake up.  So with a long processing time in Compressor the drive goes offline and then can't burn the disc, so I lose that whole session.  Turns out that Pioneer (by their own admission) is not made to be fully compatible with Macs!!  In particular Mac Pros.  I took that drive out and replaced it with an LG.  Haven't tested it yet but I'm looking forward to it.
Eric