Hi Mi Fans!
As you all already know that for flashing a fastboot ROM to Mi devices, we are using the MiFlash Tool v7.4.25 version till date. Now Xiaomi has come up with a new stable version (v2017.7.20.0) which flashes the fastboot ROM with simple one click method.
Here is the simple installation process for Miflash tool(portable):
Download the MiFlash file from the below
Process of Install
Now you are all set to flash the fastboot ROM
Credits to paramgagan