The file (ISO or UIF) ought to contain the appropriate boot image already, so burning that to disk directly should result in a bootable disk. I haven't used PowerISO, but there are plenty of good ...

I'm trying to apply an individual BIOS update to many servers. In the old days, I'd use Rufus to make a USB stick bootable, copy the BIOS update file to it, walk to the server room, plug it in, boot ...