I thought that it would be difficult but it is simple to create an EFI Partition on a USB Flash drive using a Windows PC for a Hackintosh. These are the steps that I found worked without searching for additional software.
01. Launch the Ubuntu Live CD on the PC.
02. Click “Show Applications” at the bottom left of the screen.
03. Type GParted and then launch the app.
04. Click Device on the GParted Menu.
05. Next, choose to Create Partition Table
06. Set the type to GPT and click the Apply button.
07. Click Partition on the GParted Menu.
08. Select New/Insert.
09. Enter 1 for the preceding space.
10. Enter 200 for the New size.
11. Tab four times over to the Partition name.
12. Type in EFI System Partition
13. Click the File system option
14. Select fat32
15. Type EFI for the Label and press the Add button.
16. Click Edit on the GParted Menu.
17. Select Apply All Operations.
18. Agree to the loss of data.
19. Close the Applying pending operations window.
20. Click on EFI in the Label column.
21. Click Partition on the GParted Menu.
22. Select Manage Flags in the list.
23. Click on esp once. The option boot will be chosen as well.
You are done. You can now close and exit out of Ubuntu.
As you are on Ubuntu, you will need access to Nautilus (learn more at Gixxer PC). When used correctly, Nautilus will let you unhide the ESP and give you access to use a copy and paste feature to add files for a successful boot.