Erased Windows partition with Disk Utility still can see the EFI boot on the boot screen
The drives shown as (disk image) are temporary drives stored in RAM. These drive will disappear when you leave Recovery mode.

Chasing Ghosts

You have successfully removed all windows partitions from your disks, but you have not yet removed all files added during your installation of Windows. What is left are files in your EFI partitions. The ghost is being caused by the file efi/boot/bootx64.efi stored in one of the EFI partitions.


Open a Terminal window and enter the following command.

sudo diskutil mount /dev/disk0s1

From a Finder window, open the EFI disk. Next open the EFI folder. Remove any folders named Boot or Microsoft
When finished, enter the command below.

sudo diskutil unmount /dev/disk0s1

Enter the following command.

sudo diskutil mount /dev/disk1s1

From a Finder window, open the EFI disk. Next open the EFI folder. Remove any folders named Boot or Microsoft
When finished, enter the command below.

sudo diskutil unmount /dev/disk1s1



If you booted to Recovery Mode or wish to just use a Terminal window, then enter the commands given below.

sudo  diskutil  mount  disk0s1
cd  /Volumes/EFI
rm  -fr  EFI/Windows
rm  -fr  EFI/Boot
cd  /
sudo  diskutil  unmount disk0s1
sudo  diskutil  mount  disk1s1
cd /Volumes/EFI
rm  -fr  EFI/Windows
rm  -fr  EFI/Boot
cd  /
sudo  diskutil  unmount  disk1s1