# fdisk -l (First we have to find out the partition Kali is installed on (: /dev/sda1, /dev/sda2, etc) )
# mount /dev/sda1 /mnt (Mount your kali partition)
# mount --bind /dev /mnt/dev (You will need to mount the /dev directory into mnt)
# chroot /mnt (change the root to the mounted partition to be able to run the command from the mounted partition)
# grub-install --recheck /dev/sda (install grub in the HDD sda, not sda1, sda2, etc.., just sda.
# os-prober (looks for partitions in the HDD and register them in the os-prober file.
# update-grub (Takes some templates, including the os-prober file and writes them in the menu)