Installing Windows to flash UEFI/ BIOS, then reinstalling Ubuntu

I am going to reinstall Windows on my computer so that I can flash the UEFI/ BIOS (the computer manufacturer only supplies a .exe file). I would like to efficiently reinstall Ubuntu after that. Can you explain a time efficient way to do that?

Edit: Really, I am looking for the safest way to do this with a reasonable degree of efficiency.

The most efficient way is to find a Live Windows image and boot from it.

You will be able to flash BIOS from it.

But beware that in some cases it is not a good idea to flash a new BIOS. About a week ago I flashed a new BIOS to an Asus laptop using a BIOS utility (built in into BIOS called EasyFlash).

After that I lost touchpad in Ubuntu and had other problems. I couldn't downgrade BIOS using the same utility because it didn't allow to flash older BIOS.

So I had to use a Live Windows image where I successfuly downgraded BIOS using /nodate switch.

So if you don't have a very strong reason, and everything works fine, don't upgrade BIOS. Ubuntu will take care of CPU microcode.

Disconnect your Ubuntu system drive, connect an old spare or used drive, install Windows on it, and do the BIOS update (if, as Pilot6 explained above, if you absolutely, positively, have to update the BIOS). Then, disconnect the old drive, put your Ubuntu OS drive back on, and you're ready to know, secure in the knowledge that Windows did not corrupt Linux.

The most time efficient method of putting an existing Ubuntu installation back on your system is to boot from a thumb drive, do a complete image backup of the entire drive to another (large enough) storage device, then restore that image backup after you're done with Windows.

I'll link an article on how to do this (be careful; you can erase everything as easily as backing it up), but dd is the core command for these operations.